Add project files (part 1/2)

Co-Authored-By: Claude Sonnet 5 <[email protected]>

third_party/gl/KHR/khrplatform.h

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+#ifndef __khrplatform_h_
+#define __khrplatform_h_
+
+/*
+** Copyright (c) 2008-2018 The Khronos Group Inc.
+**
+** Permission is hereby granted, free of charge, to any person obtaining a
+** copy of this software and/or associated documentation files (the
+** "Materials"), to deal in the Materials without restriction, including
+** without limitation the rights to use, copy, modify, merge, publish,
+** distribute, sublicense, and/or sell copies of the Materials, and to
+** permit persons to whom the Materials are furnished to do so, subject to
+** the following conditions:
+**
+** The above copyright notice and this permission notice shall be included
+** in all copies or substantial portions of the Materials.
+**
+** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
+*/
+
+/* Khronos platform-specific types and definitions.
+ *
+ * The master copy of khrplatform.h is maintained in the Khronos EGL
+ * Registry repository at https://github.com/KhronosGroup/EGL-Registry
+ * The last semantic modification to khrplatform.h was at commit ID:
+ *      67a3e0864c2d75ea5287b9f3d2eb74a745936692
+ *
+ * Adopters may modify this file to suit their platform. Adopters are
+ * encouraged to submit platform specific modifications to the Khronos
+ * group so that they can be included in future versions of this file.
+ * Please submit changes by filing pull requests or issues on
+ * the EGL Registry repository linked above.
+ *
+ *
+ * See the Implementer's Guidelines for information about where this file
+ * should be located on your system and for more details of its use:
+ *    http://www.khronos.org/registry/implementers_guide.pdf
+ *
+ * This file should be included as
+ *        #include <KHR/khrplatform.h>
+ * by Khronos client API header files that use its types and defines.
+ *
+ * The types in khrplatform.h should only be used to define API-specific types.
+ *
+ * Types defined in khrplatform.h:
+ *    khronos_int8_t              signed   8  bit
+ *    khronos_uint8_t             unsigned 8  bit
+ *    khronos_int16_t             signed   16 bit
+ *    khronos_uint16_t            unsigned 16 bit
+ *    khronos_int32_t             signed   32 bit
+ *    khronos_uint32_t            unsigned 32 bit
+ *    khronos_int64_t             signed   64 bit
+ *    khronos_uint64_t            unsigned 64 bit
+ *    khronos_intptr_t            signed   same number of bits as a pointer
+ *    khronos_uintptr_t           unsigned same number of bits as a pointer
+ *    khronos_ssize_t             signed   size
+ *    khronos_usize_t             unsigned size
+ *    khronos_float_t             signed   32 bit floating point
+ *    khronos_time_ns_t           unsigned 64 bit time in nanoseconds
+ *    khronos_utime_nanoseconds_t unsigned time interval or absolute time in
+ *                                         nanoseconds
+ *    khronos_stime_nanoseconds_t signed time interval in nanoseconds
+ *    khronos_boolean_enum_t      enumerated boolean type. This should
+ *      only be used as a base type when a client API's boolean type is
+ *      an enum. Client APIs which use an integer or other type for
+ *      booleans cannot use this as the base type for their boolean.
+ *
+ * Tokens defined in khrplatform.h:
+ *
+ *    KHRONOS_FALSE, KHRONOS_TRUE Enumerated boolean false/true values.
+ *
+ *    KHRONOS_SUPPORT_INT64 is 1 if 64 bit integers are supported; otherwise 0.
+ *    KHRONOS_SUPPORT_FLOAT is 1 if floats are supported; otherwise 0.
+ *
+ * Calling convention macros defined in this file:
+ *    KHRONOS_APICALL
+ *    KHRONOS_APIENTRY
+ *    KHRONOS_APIATTRIBUTES
+ *
+ * These may be used in function prototypes as:
+ *
+ *      KHRONOS_APICALL void KHRONOS_APIENTRY funcname(
+ *                                  int arg1,
+ *                                  int arg2) KHRONOS_APIATTRIBUTES;
+ */
+
+#if defined(__SCITECH_SNAP__) && !defined(KHRONOS_STATIC)
+#   define KHRONOS_STATIC 1
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APICALL
+ *-------------------------------------------------------------------------
+ * This precedes the return type of the function in the function prototype.
+ */
+#if defined(KHRONOS_STATIC)
+    /* If the preprocessor constant KHRONOS_STATIC is defined, make the
+     * header compatible with static linking. */
+#   define KHRONOS_APICALL
+#elif defined(_WIN32)
+#   define KHRONOS_APICALL __declspec(dllimport)
+#elif defined (__SYMBIAN32__)
+#   define KHRONOS_APICALL IMPORT_C
+#elif defined(__ANDROID__)
+#   define KHRONOS_APICALL __attribute__((visibility("default")))
+#else
+#   define KHRONOS_APICALL
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APIENTRY
+ *-------------------------------------------------------------------------
+ * This follows the return type of the function  and precedes the function
+ * name in the function prototype.
+ */
+#if defined(_WIN32) && !defined(_WIN32_WCE) && !defined(__SCITECH_SNAP__)
+    /* Win32 but not WinCE */
+#   define KHRONOS_APIENTRY __stdcall
+#else
+#   define KHRONOS_APIENTRY
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APIATTRIBUTES
+ *-------------------------------------------------------------------------
+ * This follows the closing parenthesis of the function prototype arguments.
+ */
+#if defined (__ARMCC_2__)
+#define KHRONOS_APIATTRIBUTES __softfp
+#else
+#define KHRONOS_APIATTRIBUTES
+#endif
+
+/*-------------------------------------------------------------------------
+ * basic type definitions
+ *-----------------------------------------------------------------------*/
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || defined(__GNUC__) || defined(__SCO__) || defined(__USLC__)
+
+
+/*
+ * Using <stdint.h>
+ */
+#include <stdint.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+/*
+ * To support platform where unsigned long cannot be used interchangeably with
+ * inptr_t (e.g. CHERI-extended ISAs), we can use the stdint.h intptr_t.
+ * Ideally, we could just use (u)intptr_t everywhere, but this could result in
+ * ABI breakage if khronos_uintptr_t is changed from unsigned long to
+ * unsigned long long or similar (this results in different C++ name mangling).
+ * To avoid changes for existing platforms, we restrict usage of intptr_t to
+ * platforms where the size of a pointer is larger than the size of long.
+ */
+#if defined(__SIZEOF_LONG__) && defined(__SIZEOF_POINTER__)
+#if __SIZEOF_POINTER__ > __SIZEOF_LONG__
+#define KHRONOS_USE_INTPTR_T
+#endif
+#endif
+
+#elif defined(__VMS ) || defined(__sgi)
+
+/*
+ * Using <inttypes.h>
+ */
+#include <inttypes.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(_WIN32) && !defined(__SCITECH_SNAP__)
+
+/*
+ * Win32
+ */
+typedef __int32                 khronos_int32_t;
+typedef unsigned __int32        khronos_uint32_t;
+typedef __int64                 khronos_int64_t;
+typedef unsigned __int64        khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(__sun__) || defined(__digital__)
+
+/*
+ * Sun or Digital
+ */
+typedef int                     khronos_int32_t;
+typedef unsigned int            khronos_uint32_t;
+#if defined(__arch64__) || defined(_LP64)
+typedef long int                khronos_int64_t;
+typedef unsigned long int       khronos_uint64_t;
+#else
+typedef long long int           khronos_int64_t;
+typedef unsigned long long int  khronos_uint64_t;
+#endif /* __arch64__ */
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif 0
+
+/*
+ * Hypothetical platform with no float or int64 support
+ */
+typedef int                     khronos_int32_t;
+typedef unsigned int            khronos_uint32_t;
+#define KHRONOS_SUPPORT_INT64   0
+#define KHRONOS_SUPPORT_FLOAT   0
+
+#else
+
+/*
+ * Generic fallback
+ */
+#include <stdint.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#endif
+
+
+/*
+ * Types that are (so far) the same on all platforms
+ */
+typedef signed   char          khronos_int8_t;
+typedef unsigned char          khronos_uint8_t;
+typedef signed   short int     khronos_int16_t;
+typedef unsigned short int     khronos_uint16_t;
+
+/*
+ * Types that differ between LLP64 and LP64 architectures - in LLP64,
+ * pointers are 64 bits, but 'long' is still 32 bits. Win64 appears
+ * to be the only LLP64 architecture in current use.
+ */
+#ifdef KHRONOS_USE_INTPTR_T
+typedef intptr_t               khronos_intptr_t;
+typedef uintptr_t              khronos_uintptr_t;
+#elif defined(_WIN64)
+typedef signed   long long int khronos_intptr_t;
+typedef unsigned long long int khronos_uintptr_t;
+#else
+typedef signed   long  int     khronos_intptr_t;
+typedef unsigned long  int     khronos_uintptr_t;
+#endif
+
+#if defined(_WIN64)
+typedef signed   long long int khronos_ssize_t;
+typedef unsigned long long int khronos_usize_t;
+#else
+typedef signed   long  int     khronos_ssize_t;
+typedef unsigned long  int     khronos_usize_t;
+#endif
+
+#if KHRONOS_SUPPORT_FLOAT
+/*
+ * Float type
+ */
+typedef          float         khronos_float_t;
+#endif
+
+#if KHRONOS_SUPPORT_INT64
+/* Time types
+ *
+ * These types can be used to represent a time interval in nanoseconds or
+ * an absolute Unadjusted System Time.  Unadjusted System Time is the number
+ * of nanoseconds since some arbitrary system event (e.g. since the last
+ * time the system booted).  The Unadjusted System Time is an unsigned
+ * 64 bit value that wraps back to 0 every 584 years.  Time intervals
+ * may be either signed or unsigned.
+ */
+typedef khronos_uint64_t       khronos_utime_nanoseconds_t;
+typedef khronos_int64_t        khronos_stime_nanoseconds_t;
+#endif
+
+/*
+ * Dummy value used to pad enum types to 32 bits.
+ */
+#ifndef KHRONOS_MAX_ENUM
+#define KHRONOS_MAX_ENUM 0x7FFFFFFF
+#endif
+
+/*
+ * Enumerated boolean type
+ *
+ * Values other than zero should be considered to be true.  Therefore
+ * comparisons should not be made against KHRONOS_TRUE.
+ */
+typedef enum {
+    KHRONOS_FALSE = 0,
+    KHRONOS_TRUE  = 1,
+    KHRONOS_BOOLEAN_ENUM_FORCE_SIZE = KHRONOS_MAX_ENUM
+} khronos_boolean_enum_t;
+
+#endif /* __khrplatform_h_ */

third_party/minicrt/include/assert.h

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+#pragma once
+#define assert(x) ((void)0)

third_party/minicrt/include/math.h

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+#pragma once
+#ifdef __cplusplus
+extern "C" {
+#endif
+double sin(double); double cos(double); double tan(double); double acos(double); double asin(double); double atan(double);
+double atan2(double, double); double sqrt(double); double pow(double, double); double fabs(double); double floor(double);
+double ceil(double); double fmod(double, double); double log(double); double exp(double); double ldexp(double, int);
+float sinf(float); float cosf(float); float tanf(float); float acosf(float); float atan2f(float, float); float sqrtf(float);
+float expf(float); float powf(float, float); float fabsf(float); float floorf(float); float ceilf(float); float fmodf(float, float);
+#ifdef __cplusplus
+}
+#endif

third_party/minicrt/include/memory.h

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+#pragma once
+#include <string.h>

third_party/minicrt/include/stdio.h

@@ -0,0 +1,24 @@
+#pragma once
+#include <stddef.h>
+#include <stdarg.h>
+#ifdef __cplusplus
+extern "C" {
+#endif
+typedef struct _iobuf FILE;
+FILE *fopen(const char *, const char *);
+int fclose(FILE *);
+size_t fread(void *, size_t, size_t, FILE *);
+int fseek(FILE *, long, int);
+int feof(FILE *);
+int fopen_s(FILE **, const char *, const char *);
+long ftell(FILE *);
+int sprintf(char *, const char *, ...);
+int snprintf(char *, size_t, const char *, ...);
+// diagnostics printing of the bundled libraries is not wanted in the client
+#define printf(...) ((void)0)
+#define SEEK_SET 0
+#define SEEK_CUR 1
+#define SEEK_END 2
+#ifdef __cplusplus
+}
+#endif

third_party/minicrt/include/stdlib.h

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+// Declarations of the UCRT functions the bundled C libraries (NanoVG, stb) use; the cross build has no Windows SDK.
+#pragma once
+#include <stddef.h>
+#ifdef __cplusplus
+extern "C" {
+#endif
+void *malloc(size_t);
+void *calloc(size_t, size_t);
+void *realloc(void *, size_t);
+void free(void *);
+void qsort(void *, size_t, size_t, int (*)(const void *, const void *));
+int abs(int);
+double strtod(const char *, char **);
+long strtol(const char *, char **, int);
+#ifdef __cplusplus
+}
+#endif

third_party/minicrt/include/string.h

@@ -0,0 +1,18 @@
+#pragma once
+#include <stddef.h>
+#ifdef __cplusplus
+extern "C" {
+#endif
+void *memcpy(void *, const void *, size_t);
+void *memmove(void *, const void *, size_t);
+void *memset(void *, int, size_t);
+int memcmp(const void *, const void *, size_t);
+size_t strlen(const char *);
+int strcmp(const char *, const char *);
+int strncmp(const char *, const char *, size_t);
+char *strcpy(char *, const char *);
+char *strncpy(char *, const char *, size_t);
+char *strchr(const char *, int);
+#ifdef __cplusplus
+}
+#endif

third_party/nanovg/.github/workflows/ci.yml

@@ -0,0 +1,28 @@
+name: CI
+
+on: [push]
+
+env:
+  BUILD_TYPE: release
+
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ ubuntu-latest]
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Install required packages
+      run: sudo apt-get install premake4 build-essential libglfw3-dev libglew-dev pkg-config
+
+    - name: Premake
+      run:  premake4 gmake
+
+# due to glew problems with in the current ubuntu-latest, we don't build the examples (yet)
+# https://github.com/openai/mujoco-py/issues/383 has the same problem for reference
+# this doesn't happen in focal 
+    - name: Make
+      run:  cd build && make nanovg 

third_party/nanovg/.gitignore

@@ -0,0 +1,28 @@
+## Compiled source #
+*.com
+*.class
+*.dll
+*.exe
+*.o
+*.so
+test
+
+## Logs and databases #
+*.log
+*.sql
+*.sqlite
+
+## OS generated files #
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+ehthumbs.db
+Thumbs.db
+
+## Build dir
+build/*
+
+## xcode specific
+*xcuserdata*

third_party/nanovg/LICENSE.txt

@@ -0,0 +1,18 @@
+Copyright (c) 2013 Mikko Mononen [email protected]
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+claim that you wrote the original software. If you use this software
+in a product, an acknowledgment in the product documentation would be
+appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+

third_party/nanovg/README.md

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+*This project is not actively maintained.*
+
+NanoVG
+==========
+
+NanoVG is small antialiased vector graphics rendering library for OpenGL. It has lean API modeled after HTML5 canvas API. It is aimed to be a practical and fun toolset for building scalable user interfaces and visualizations.
+
+## Screenshot
+
+![screenshot of some text rendered witht the sample program](/example/screenshot-01.png?raw=true)
+
+Usage
+=====
+
+The NanoVG API is modeled loosely on HTML5 canvas API. If you know canvas, you're up to speed with NanoVG in no time.
+
+## Creating drawing context
+
+The drawing context is created using platform specific constructor function. If you're using the OpenGL 2.0 back-end the context is created as follows:
+```C
+#define NANOVG_GL2_IMPLEMENTATION	// Use GL2 implementation.
+#include "nanovg_gl.h"
+...
+struct NVGcontext* vg = nvgCreateGL2(NVG_ANTIALIAS | NVG_STENCIL_STROKES);
+```
+
+The first parameter defines flags for creating the renderer.
+
+- `NVG_ANTIALIAS` means that the renderer adjusts the geometry to include anti-aliasing. If you're using MSAA, you can omit this flags. 
+- `NVG_STENCIL_STROKES` means that the render uses better quality rendering for (overlapping) strokes. The quality is mostly visible on wider strokes. If you want speed, you can omit this flag.
+
+Currently there is an OpenGL back-end for NanoVG: [nanovg_gl.h](/src/nanovg_gl.h) for OpenGL 2.0, OpenGL ES 2.0, OpenGL 3.2 core profile and OpenGL ES 3. The implementation can be chosen using a define as in above example. See the header file and examples for further info. 
+
+*NOTE:* The render target you're rendering to must have stencil buffer.
+
+## Drawing shapes with NanoVG
+
+Drawing a simple shape using NanoVG consists of four steps: 1) begin a new shape, 2) define the path to draw, 3) set fill or stroke, 4) and finally fill or stroke the path.
+
+```C
+nvgBeginPath(vg);
+nvgRect(vg, 100,100, 120,30);
+nvgFillColor(vg, nvgRGBA(255,192,0,255));
+nvgFill(vg);
+```
+
+Calling `nvgBeginPath()` will clear any existing paths and start drawing from blank slate. There are number of number of functions to define the path to draw, such as rectangle, rounded rectangle and ellipse, or you can use the common moveTo, lineTo, bezierTo and arcTo API to compose the paths step by step.
+
+## Understanding Composite Paths
+
+Because of the way the rendering backend is build in NanoVG, drawing a composite path, that is path consisting from multiple paths defining holes and fills, is a bit more involved. NanoVG uses even-odd filling rule and by default the paths are wound in counter clockwise order. Keep that in mind when drawing using the low level draw API. In order to wind one of the predefined shapes as a hole, you should call `nvgPathWinding(vg, NVG_HOLE)`, or `nvgPathWinding(vg, NVG_CW)` _after_ defining the path.
+
+``` C
+nvgBeginPath(vg);
+nvgRect(vg, 100,100, 120,30);
+nvgCircle(vg, 120,120, 5);
+nvgPathWinding(vg, NVG_HOLE);	// Mark circle as a hole.
+nvgFillColor(vg, nvgRGBA(255,192,0,255));
+nvgFill(vg);
+```
+
+## Rendering is wrong, what to do?
+
+- make sure you have created NanoVG context using one of the `nvgCreatexxx()` calls
+- make sure you have initialised OpenGL with *stencil buffer*
+- make sure you have cleared stencil buffer
+- make sure all rendering calls happen between `nvgBeginFrame()` and `nvgEndFrame()`
+- to enable more checks for OpenGL errors, add `NVG_DEBUG` flag to `nvgCreatexxx()`
+- if the problem still persists, please report an issue!
+
+## OpenGL state touched by the backend
+
+The OpenGL back-end touches following states:
+
+When textures are uploaded or updated, the following pixel store is set to defaults: `GL_UNPACK_ALIGNMENT`, `GL_UNPACK_ROW_LENGTH`, `GL_UNPACK_SKIP_PIXELS`, `GL_UNPACK_SKIP_ROWS`. Texture binding is also affected. Texture updates can happen when the user loads images, or when new font glyphs are added. Glyphs are added as needed between calls to  `nvgBeginFrame()` and `nvgEndFrame()`.
+
+The data for the whole frame is buffered and flushed in `nvgEndFrame()`. The following code illustrates the OpenGL state touched by the rendering code:
+```C
+	glUseProgram(prog);
+	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+	glEnable(GL_CULL_FACE);
+	glCullFace(GL_BACK);
+	glFrontFace(GL_CCW);
+	glEnable(GL_BLEND);
+	glDisable(GL_DEPTH_TEST);
+	glDisable(GL_SCISSOR_TEST);
+	glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+	glStencilMask(0xffffffff);
+	glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
+	glStencilFunc(GL_ALWAYS, 0, 0xffffffff);
+	glActiveTexture(GL_TEXTURE0);
+	glBindBuffer(GL_UNIFORM_BUFFER, buf);
+	glBindVertexArray(arr);
+	glBindBuffer(GL_ARRAY_BUFFER, buf);
+	glBindTexture(GL_TEXTURE_2D, tex);
+	glUniformBlockBinding(... , GLNVG_FRAG_BINDING);
+```
+
+## API Reference
+
+See the header file [nanovg.h](/src/nanovg.h) for API reference.
+
+## Ports
+
+- [DX11 port](https://github.com/cmaughan/nanovg) by [Chris Maughan](https://github.com/cmaughan)
+- [Metal port](https://github.com/ollix/MetalNanoVG) by [Olli Wang](https://github.com/olliwang)
+- [bgfx port](https://github.com/bkaradzic/bgfx/tree/master/examples/20-nanovg) by [Branimir Karadžić](https://github.com/bkaradzic)
+
+## Projects using NanoVG
+
+- [Processing API simulation by vinjn](https://github.com/island-org/island/blob/master/include/sketch2d.h)
+- [NanoVG for .NET, C# P/Invoke binding](https://github.com/sbarisic/nanovg_dotnet)
+
+## License
+The library is licensed under [zlib license](LICENSE.txt)
+Fonts used in examples:
+- Roboto licensed under [Apache license](http://www.apache.org/licenses/LICENSE-2.0)
+- Entypo licensed under CC BY-SA 4.0.
+- Noto Emoji licensed under [SIL Open Font License, Version 1.1](http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL)
+
+## Discussions
+[NanoVG mailing list](https://groups.google.com/forum/#!forum/nanovg)
+
+## Links
+Uses [stb_truetype](http://nothings.org) (or, optionally, [freetype](http://freetype.org)) for font rendering.
+Uses [stb_image](http://nothings.org) for image loading.

third_party/nanovg/src/nanovg.h

@@ -0,0 +1,697 @@
+//
+// Copyright (c) 2013 Mikko Mononen [email protected]
+//
+// This software is provided 'as-is', without any express or implied
+// warranty.  In no event will the authors be held liable for any damages
+// arising from the use of this software.
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+// 1. The origin of this software must not be misrepresented; you must not
+//    claim that you wrote the original software. If you use this software
+//    in a product, an acknowledgment in the product documentation would be
+//    appreciated but is not required.
+// 2. Altered source versions must be plainly marked as such, and must not be
+//    misrepresented as being the original software.
+// 3. This notice may not be removed or altered from any source distribution.
+//
+
+#ifndef NANOVG_H
+#define NANOVG_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define NVG_PI 3.14159265358979323846264338327f
+
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4201)  // nonstandard extension used : nameless struct/union
+#endif
+
+typedef struct NVGcontext NVGcontext;
+
+struct NVGcolor {
+	union {
+		float rgba[4];
+		struct {
+			float r,g,b,a;
+		};
+	};
+};
+typedef struct NVGcolor NVGcolor;
+
+struct NVGpaint {
+	float xform[6];
+	float extent[2];
+	float radius;
+	float feather;
+	NVGcolor innerColor;
+	NVGcolor outerColor;
+	int image;
+};
+typedef struct NVGpaint NVGpaint;
+
+enum NVGwinding {
+	NVG_CCW = 1,			// Winding for solid shapes
+	NVG_CW = 2,				// Winding for holes
+};
+
+enum NVGsolidity {
+	NVG_SOLID = 1,			// CCW
+	NVG_HOLE = 2,			// CW
+};
+
+enum NVGlineCap {
+	NVG_BUTT,
+	NVG_ROUND,
+	NVG_SQUARE,
+	NVG_BEVEL,
+	NVG_MITER,
+};
+
+enum NVGalign {
+	// Horizontal align
+	NVG_ALIGN_LEFT 		= 1<<0,	// Default, align text horizontally to left.
+	NVG_ALIGN_CENTER 	= 1<<1,	// Align text horizontally to center.
+	NVG_ALIGN_RIGHT 	= 1<<2,	// Align text horizontally to right.
+	// Vertical align
+	NVG_ALIGN_TOP 		= 1<<3,	// Align text vertically to top.
+	NVG_ALIGN_MIDDLE	= 1<<4,	// Align text vertically to middle.
+	NVG_ALIGN_BOTTOM	= 1<<5,	// Align text vertically to bottom.
+	NVG_ALIGN_BASELINE	= 1<<6, // Default, align text vertically to baseline.
+};
+
+enum NVGblendFactor {
+	NVG_ZERO = 1<<0,
+	NVG_ONE = 1<<1,
+	NVG_SRC_COLOR = 1<<2,
+	NVG_ONE_MINUS_SRC_COLOR = 1<<3,
+	NVG_DST_COLOR = 1<<4,
+	NVG_ONE_MINUS_DST_COLOR = 1<<5,
+	NVG_SRC_ALPHA = 1<<6,
+	NVG_ONE_MINUS_SRC_ALPHA = 1<<7,
+	NVG_DST_ALPHA = 1<<8,
+	NVG_ONE_MINUS_DST_ALPHA = 1<<9,
+	NVG_SRC_ALPHA_SATURATE = 1<<10,
+};
+
+enum NVGcompositeOperation {
+	NVG_SOURCE_OVER,
+	NVG_SOURCE_IN,
+	NVG_SOURCE_OUT,
+	NVG_ATOP,
+	NVG_DESTINATION_OVER,
+	NVG_DESTINATION_IN,
+	NVG_DESTINATION_OUT,
+	NVG_DESTINATION_ATOP,
+	NVG_LIGHTER,
+	NVG_COPY,
+	NVG_XOR,
+};
+
+struct NVGcompositeOperationState {
+	int srcRGB;
+	int dstRGB;
+	int srcAlpha;
+	int dstAlpha;
+};
+typedef struct NVGcompositeOperationState NVGcompositeOperationState;
+
+struct NVGglyphPosition {
+	const char* str;	// Position of the glyph in the input string.
+	float x;			// The x-coordinate of the logical glyph position.
+	float minx, maxx;	// The bounds of the glyph shape.
+};
+typedef struct NVGglyphPosition NVGglyphPosition;
+
+struct NVGtextRow {
+	const char* start;	// Pointer to the input text where the row starts.
+	const char* end;	// Pointer to the input text where the row ends (one past the last character).
+	const char* next;	// Pointer to the beginning of the next row.
+	float width;		// Logical width of the row.
+	float minx, maxx;	// Actual bounds of the row. Logical with and bounds can differ because of kerning and some parts over extending.
+};
+typedef struct NVGtextRow NVGtextRow;
+
+enum NVGimageFlags {
+    NVG_IMAGE_GENERATE_MIPMAPS	= 1<<0,     // Generate mipmaps during creation of the image.
+	NVG_IMAGE_REPEATX			= 1<<1,		// Repeat image in X direction.
+	NVG_IMAGE_REPEATY			= 1<<2,		// Repeat image in Y direction.
+	NVG_IMAGE_FLIPY				= 1<<3,		// Flips (inverses) image in Y direction when rendered.
+	NVG_IMAGE_PREMULTIPLIED		= 1<<4,		// Image data has premultiplied alpha.
+	NVG_IMAGE_NEAREST			= 1<<5,		// Image interpolation is Nearest instead Linear
+};
+
+// Begin drawing a new frame
+// Calls to nanovg drawing API should be wrapped in nvgBeginFrame() & nvgEndFrame()
+// nvgBeginFrame() defines the size of the window to render to in relation currently
+// set viewport (i.e. glViewport on GL backends). Device pixel ration allows to
+// control the rendering on Hi-DPI devices.
+// For example, GLFW returns two dimension for an opened window: window size and
+// frame buffer size. In that case you would set windowWidth/Height to the window size
+// devicePixelRatio to: frameBufferWidth / windowWidth.
+void nvgBeginFrame(NVGcontext* ctx, float windowWidth, float windowHeight, float devicePixelRatio);
+
+// Cancels drawing the current frame.
+void nvgCancelFrame(NVGcontext* ctx);
+
+// Ends drawing flushing remaining render state.
+void nvgEndFrame(NVGcontext* ctx);
+
+//
+// Composite operation
+//
+// The composite operations in NanoVG are modeled after HTML Canvas API, and
+// the blend func is based on OpenGL (see corresponding manuals for more info).
+// The colors in the blending state have premultiplied alpha.
+
+// Sets the composite operation. The op parameter should be one of NVGcompositeOperation.
+void nvgGlobalCompositeOperation(NVGcontext* ctx, int op);
+
+// Sets the composite operation with custom pixel arithmetic. The parameters should be one of NVGblendFactor.
+void nvgGlobalCompositeBlendFunc(NVGcontext* ctx, int sfactor, int dfactor);
+
+// Sets the composite operation with custom pixel arithmetic for RGB and alpha components separately. The parameters should be one of NVGblendFactor.
+void nvgGlobalCompositeBlendFuncSeparate(NVGcontext* ctx, int srcRGB, int dstRGB, int srcAlpha, int dstAlpha);
+
+//
+// Color utils
+//
+// Colors in NanoVG are stored as unsigned ints in ABGR format.
+
+// Returns a color value from red, green, blue values. Alpha will be set to 255 (1.0f).
+NVGcolor nvgRGB(unsigned char r, unsigned char g, unsigned char b);
+
+// Returns a color value from red, green, blue values. Alpha will be set to 1.0f.
+NVGcolor nvgRGBf(float r, float g, float b);
+
+
+// Returns a color value from red, green, blue and alpha values.
+NVGcolor nvgRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
+
+// Returns a color value from red, green, blue and alpha values.
+NVGcolor nvgRGBAf(float r, float g, float b, float a);
+
+
+// Linearly interpolates from color c0 to c1, and returns resulting color value.
+NVGcolor nvgLerpRGBA(NVGcolor c0, NVGcolor c1, float u);
+
+// Sets transparency of a color value.
+NVGcolor nvgTransRGBA(NVGcolor c0, unsigned char a);
+
+// Sets transparency of a color value.
+NVGcolor nvgTransRGBAf(NVGcolor c0, float a);
+
+// Returns color value specified by hue, saturation and lightness.
+// HSL values are all in range [0..1], alpha will be set to 255.
+NVGcolor nvgHSL(float h, float s, float l);
+
+// Returns color value specified by hue, saturation and lightness and alpha.
+// HSL values are all in range [0..1], alpha in range [0..255]
+NVGcolor nvgHSLA(float h, float s, float l, unsigned char a);
+
+//
+// State Handling
+//
+// NanoVG contains state which represents how paths will be rendered.
+// The state contains transform, fill and stroke styles, text and font styles,
+// and scissor clipping.
+
+// Pushes and saves the current render state into a state stack.
+// A matching nvgRestore() must be used to restore the state.
+void nvgSave(NVGcontext* ctx);
+
+// Pops and restores current render state.
+void nvgRestore(NVGcontext* ctx);
+
+// Resets current render state to default values. Does not affect the render state stack.
+void nvgReset(NVGcontext* ctx);
+
+//
+// Render styles
+//
+// Fill and stroke render style can be either a solid color or a paint which is a gradient or a pattern.
+// Solid color is simply defined as a color value, different kinds of paints can be created
+// using nvgLinearGradient(), nvgBoxGradient(), nvgRadialGradient() and nvgImagePattern().
+//
+// Current render style can be saved and restored using nvgSave() and nvgRestore().
+
+// Sets whether to draw antialias for nvgStroke() and nvgFill(). It's enabled by default.
+void nvgShapeAntiAlias(NVGcontext* ctx, int enabled);
+
+// Sets current stroke style to a solid color.
+void nvgStrokeColor(NVGcontext* ctx, NVGcolor color);
+
+// Sets current stroke style to a paint, which can be a one of the gradients or a pattern.
+void nvgStrokePaint(NVGcontext* ctx, NVGpaint paint);
+
+// Sets current fill style to a solid color.
+void nvgFillColor(NVGcontext* ctx, NVGcolor color);
+
+// Sets current fill style to a paint, which can be a one of the gradients or a pattern.
+void nvgFillPaint(NVGcontext* ctx, NVGpaint paint);
+
+// Sets the miter limit of the stroke style.
+// Miter limit controls when a sharp corner is beveled.
+void nvgMiterLimit(NVGcontext* ctx, float limit);
+
+// Sets the stroke width of the stroke style.
+void nvgStrokeWidth(NVGcontext* ctx, float size);
+
+// Sets how the end of the line (cap) is drawn,
+// Can be one of: NVG_BUTT (default), NVG_ROUND, NVG_SQUARE.
+void nvgLineCap(NVGcontext* ctx, int cap);
+
+// Sets how sharp path corners are drawn.
+// Can be one of NVG_MITER (default), NVG_ROUND, NVG_BEVEL.
+void nvgLineJoin(NVGcontext* ctx, int join);
+
+// Sets the transparency applied to all rendered shapes.
+// Already transparent paths will get proportionally more transparent as well.
+void nvgGlobalAlpha(NVGcontext* ctx, float alpha);
+
+//
+// Transforms
+//
+// The paths, gradients, patterns and scissor region are transformed by an transformation
+// matrix at the time when they are passed to the API.
+// The current transformation matrix is a affine matrix:
+//   [sx kx tx]
+//   [ky sy ty]
+//   [ 0  0  1]
+// Where: sx,sy define scaling, kx,ky skewing, and tx,ty translation.
+// The last row is assumed to be 0,0,1 and is not stored.
+//
+// Apart from nvgResetTransform(), each transformation function first creates
+// specific transformation matrix and pre-multiplies the current transformation by it.
+//
+// Current coordinate system (transformation) can be saved and restored using nvgSave() and nvgRestore().
+
+// Resets current transform to a identity matrix.
+void nvgResetTransform(NVGcontext* ctx);
+
+// Premultiplies current coordinate system by specified matrix.
+// The parameters are interpreted as matrix as follows:
+//   [a c e]
+//   [b d f]
+//   [0 0 1]
+void nvgTransform(NVGcontext* ctx, float a, float b, float c, float d, float e, float f);
+
+// Translates current coordinate system.
+void nvgTranslate(NVGcontext* ctx, float x, float y);
+
+// Rotates current coordinate system. Angle is specified in radians.
+void nvgRotate(NVGcontext* ctx, float angle);
+
+// Skews the current coordinate system along X axis. Angle is specified in radians.
+void nvgSkewX(NVGcontext* ctx, float angle);
+
+// Skews the current coordinate system along Y axis. Angle is specified in radians.
+void nvgSkewY(NVGcontext* ctx, float angle);
+
+// Scales the current coordinate system.
+void nvgScale(NVGcontext* ctx, float x, float y);
+
+// Stores the top part (a-f) of the current transformation matrix in to the specified buffer.
+//   [a c e]
+//   [b d f]
+//   [0 0 1]
+// There should be space for 6 floats in the return buffer for the values a-f.
+void nvgCurrentTransform(NVGcontext* ctx, float* xform);
+
+
+// The following functions can be used to make calculations on 2x3 transformation matrices.
+// A 2x3 matrix is represented as float[6].
+
+// Sets the transform to identity matrix.
+void nvgTransformIdentity(float* dst);
+
+// Sets the transform to translation matrix matrix.
+void nvgTransformTranslate(float* dst, float tx, float ty);
+
+// Sets the transform to scale matrix.
+void nvgTransformScale(float* dst, float sx, float sy);
+
+// Sets the transform to rotate matrix. Angle is specified in radians.
+void nvgTransformRotate(float* dst, float a);
+
+// Sets the transform to skew-x matrix. Angle is specified in radians.
+void nvgTransformSkewX(float* dst, float a);
+
+// Sets the transform to skew-y matrix. Angle is specified in radians.
+void nvgTransformSkewY(float* dst, float a);
+
+// Sets the transform to the result of multiplication of two transforms, of A = A*B.
+void nvgTransformMultiply(float* dst, const float* src);
+
+// Sets the transform to the result of multiplication of two transforms, of A = B*A.
+void nvgTransformPremultiply(float* dst, const float* src);
+
+// Sets the destination to inverse of specified transform.
+// Returns 1 if the inverse could be calculated, else 0.
+int nvgTransformInverse(float* dst, const float* src);
+
+// Transform a point by given transform.
+void nvgTransformPoint(float* dstx, float* dsty, const float* xform, float srcx, float srcy);
+
+// Converts degrees to radians and vice versa.
+float nvgDegToRad(float deg);
+float nvgRadToDeg(float rad);
+
+//
+// Images
+//
+// NanoVG allows you to load jpg, png, psd, tga, pic and gif files to be used for rendering.
+// In addition you can upload your own image. The image loading is provided by stb_image.
+// The parameter imageFlags is combination of flags defined in NVGimageFlags.
+
+// Creates image by loading it from the disk from specified file name.
+// Returns handle to the image.
+int nvgCreateImage(NVGcontext* ctx, const char* filename, int imageFlags);
+
+// Creates image by loading it from the specified chunk of memory.
+// Returns handle to the image.
+int nvgCreateImageMem(NVGcontext* ctx, int imageFlags, unsigned char* data, int ndata);
+
+// Creates image from specified image data.
+// Returns handle to the image.
+int nvgCreateImageRGBA(NVGcontext* ctx, int w, int h, int imageFlags, const unsigned char* data);
+
+// Updates image data specified by image handle.
+void nvgUpdateImage(NVGcontext* ctx, int image, const unsigned char* data);
+
+// Returns the dimensions of a created image.
+void nvgImageSize(NVGcontext* ctx, int image, int* w, int* h);
+
+// Deletes created image.
+void nvgDeleteImage(NVGcontext* ctx, int image);
+
+//
+// Paints
+//
+// NanoVG supports four types of paints: linear gradient, box gradient, radial gradient and image pattern.
+// These can be used as paints for strokes and fills.
+
+// Creates and returns a linear gradient. Parameters (sx,sy)-(ex,ey) specify the start and end coordinates
+// of the linear gradient, icol specifies the start color and ocol the end color.
+// The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
+NVGpaint nvgLinearGradient(NVGcontext* ctx, float sx, float sy, float ex, float ey,
+						   NVGcolor icol, NVGcolor ocol);
+
+// Creates and returns a box gradient. Box gradient is a feathered rounded rectangle, it is useful for rendering
+// drop shadows or highlights for boxes. Parameters (x,y) define the top-left corner of the rectangle,
+// (w,h) define the size of the rectangle, r defines the corner radius, and f feather. Feather defines how blurry
+// the border of the rectangle is. Parameter icol specifies the inner color and ocol the outer color of the gradient.
+// The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
+NVGpaint nvgBoxGradient(NVGcontext* ctx, float x, float y, float w, float h,
+						float r, float f, NVGcolor icol, NVGcolor ocol);
+
+// Creates and returns a radial gradient. Parameters (cx,cy) specify the center, inr and outr specify
+// the inner and outer radius of the gradient, icol specifies the start color and ocol the end color.
+// The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
+NVGpaint nvgRadialGradient(NVGcontext* ctx, float cx, float cy, float inr, float outr,
+						   NVGcolor icol, NVGcolor ocol);
+
+// Creates and returns an image pattern. Parameters (ox,oy) specify the left-top location of the image pattern,
+// (ex,ey) the size of one image, angle rotation around the top-left corner, image is handle to the image to render.
+// The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
+NVGpaint nvgImagePattern(NVGcontext* ctx, float ox, float oy, float ex, float ey,
+						 float angle, int image, float alpha);
+
+//
+// Scissoring
+//
+// Scissoring allows you to clip the rendering into a rectangle. This is useful for various
+// user interface cases like rendering a text edit or a timeline.
+
+// Sets the current scissor rectangle.
+// The scissor rectangle is transformed by the current transform.
+void nvgScissor(NVGcontext* ctx, float x, float y, float w, float h);
+
+// Intersects current scissor rectangle with the specified rectangle.
+// The scissor rectangle is transformed by the current transform.
+// Note: in case the rotation of previous scissor rect differs from
+// the current one, the intersection will be done between the specified
+// rectangle and the previous scissor rectangle transformed in the current
+// transform space. The resulting shape is always rectangle.
+void nvgIntersectScissor(NVGcontext* ctx, float x, float y, float w, float h);
+
+// Reset and disables scissoring.
+void nvgResetScissor(NVGcontext* ctx);
+
+//
+// Paths
+//
+// Drawing a new shape starts with nvgBeginPath(), it clears all the currently defined paths.
+// Then you define one or more paths and sub-paths which describe the shape. The are functions
+// to draw common shapes like rectangles and circles, and lower level step-by-step functions,
+// which allow to define a path curve by curve.
+//
+// NanoVG uses even-odd fill rule to draw the shapes. Solid shapes should have counter clockwise
+// winding and holes should have counter clockwise order. To specify winding of a path you can
+// call nvgPathWinding(). This is useful especially for the common shapes, which are drawn CCW.
+//
+// Finally you can fill the path using current fill style by calling nvgFill(), and stroke it
+// with current stroke style by calling nvgStroke().
+//
+// The curve segments and sub-paths are transformed by the current transform.
+
+// Clears the current path and sub-paths.
+void nvgBeginPath(NVGcontext* ctx);
+
+// Starts new sub-path with specified point as first point.
+void nvgMoveTo(NVGcontext* ctx, float x, float y);
+
+// Adds line segment from the last point in the path to the specified point.
+void nvgLineTo(NVGcontext* ctx, float x, float y);
+
+// Adds cubic bezier segment from last point in the path via two control points to the specified point.
+void nvgBezierTo(NVGcontext* ctx, float c1x, float c1y, float c2x, float c2y, float x, float y);
+
+// Adds quadratic bezier segment from last point in the path via a control point to the specified point.
+void nvgQuadTo(NVGcontext* ctx, float cx, float cy, float x, float y);
+
+// Adds an arc segment at the corner defined by the last path point, and two specified points.
+void nvgArcTo(NVGcontext* ctx, float x1, float y1, float x2, float y2, float radius);
+
+// Closes current sub-path with a line segment.
+void nvgClosePath(NVGcontext* ctx);
+
+// Sets the current sub-path winding, see NVGwinding and NVGsolidity.
+void nvgPathWinding(NVGcontext* ctx, int dir);
+
+// Creates new circle arc shaped sub-path. The arc center is at cx,cy, the arc radius is r,
+// and the arc is drawn from angle a0 to a1, and swept in direction dir (NVG_CCW, or NVG_CW).
+// Angles are specified in radians.
+void nvgArc(NVGcontext* ctx, float cx, float cy, float r, float a0, float a1, int dir);
+
+// Creates new rectangle shaped sub-path.
+void nvgRect(NVGcontext* ctx, float x, float y, float w, float h);
+
+// Creates new rounded rectangle shaped sub-path.
+void nvgRoundedRect(NVGcontext* ctx, float x, float y, float w, float h, float r);
+
+// Creates new rounded rectangle shaped sub-path with varying radii for each corner.
+void nvgRoundedRectVarying(NVGcontext* ctx, float x, float y, float w, float h, float radTopLeft, float radTopRight, float radBottomRight, float radBottomLeft);
+
+// Creates new ellipse shaped sub-path.
+void nvgEllipse(NVGcontext* ctx, float cx, float cy, float rx, float ry);
+
+// Creates new circle shaped sub-path.
+void nvgCircle(NVGcontext* ctx, float cx, float cy, float r);
+
+// Fills the current path with current fill style.
+void nvgFill(NVGcontext* ctx);
+
+// Fills the current path with current stroke style.
+void nvgStroke(NVGcontext* ctx);
+
+
+//
+// Text
+//
+// NanoVG allows you to load .ttf files and use the font to render text.
+//
+// The appearance of the text can be defined by setting the current text style
+// and by specifying the fill color. Common text and font settings such as
+// font size, letter spacing and text align are supported. Font blur allows you
+// to create simple text effects such as drop shadows.
+//
+// At render time the font face can be set based on the font handles or name.
+//
+// Font measure functions return values in local space, the calculations are
+// carried in the same resolution as the final rendering. This is done because
+// the text glyph positions are snapped to the nearest pixels sharp rendering.
+//
+// The local space means that values are not rotated or scale as per the current
+// transformation. For example if you set font size to 12, which would mean that
+// line height is 16, then regardless of the current scaling and rotation, the
+// returned line height is always 16. Some measures may vary because of the scaling
+// since aforementioned pixel snapping.
+//
+// While this may sound a little odd, the setup allows you to always render the
+// same way regardless of scaling. I.e. following works regardless of scaling:
+//
+//		const char* txt = "Text me up.";
+//		nvgTextBounds(vg, x,y, txt, NULL, bounds);
+//		nvgBeginPath(vg);
+//		nvgRect(vg, bounds[0],bounds[1], bounds[2]-bounds[0], bounds[3]-bounds[1]);
+//		nvgFill(vg);
+//
+// Note: currently only solid color fill is supported for text.
+
+// Creates font by loading it from the disk from specified file name.
+// Returns handle to the font.
+int nvgCreateFont(NVGcontext* ctx, const char* name, const char* filename);
+
+// fontIndex specifies which font face to load from a .ttf/.ttc file.
+int nvgCreateFontAtIndex(NVGcontext* ctx, const char* name, const char* filename, const int fontIndex);
+
+// Creates font by loading it from the specified memory chunk.
+// Returns handle to the font.
+int nvgCreateFontMem(NVGcontext* ctx, const char* name, unsigned char* data, int ndata, int freeData);
+
+// fontIndex specifies which font face to load from a .ttf/.ttc file.
+int nvgCreateFontMemAtIndex(NVGcontext* ctx, const char* name, unsigned char* data, int ndata, int freeData, const int fontIndex);
+
+// Finds a loaded font of specified name, and returns handle to it, or -1 if the font is not found.
+int nvgFindFont(NVGcontext* ctx, const char* name);
+
+// Adds a fallback font by handle.
+int nvgAddFallbackFontId(NVGcontext* ctx, int baseFont, int fallbackFont);
+
+// Adds a fallback font by name.
+int nvgAddFallbackFont(NVGcontext* ctx, const char* baseFont, const char* fallbackFont);
+
+// Resets fallback fonts by handle.
+void nvgResetFallbackFontsId(NVGcontext* ctx, int baseFont);
+
+// Resets fallback fonts by name.
+void nvgResetFallbackFonts(NVGcontext* ctx, const char* baseFont);
+
+// Sets the font size of current text style.
+void nvgFontSize(NVGcontext* ctx, float size);
+
+// Sets the blur of current text style.
+void nvgFontBlur(NVGcontext* ctx, float blur);
+
+// Sets the letter spacing of current text style.
+void nvgTextLetterSpacing(NVGcontext* ctx, float spacing);
+
+// Sets the proportional line height of current text style. The line height is specified as multiple of font size.
+void nvgTextLineHeight(NVGcontext* ctx, float lineHeight);
+
+// Sets the text align of current text style, see NVGalign for options.
+void nvgTextAlign(NVGcontext* ctx, int align);
+
+// Sets the font face based on specified id of current text style.
+void nvgFontFaceId(NVGcontext* ctx, int font);
+
+// Sets the font face based on specified name of current text style.
+void nvgFontFace(NVGcontext* ctx, const char* font);
+
+// Draws text string at specified location. If end is specified only the sub-string up to the end is drawn.
+float nvgText(NVGcontext* ctx, float x, float y, const char* string, const char* end);
+
+// Draws multi-line text string at specified location wrapped at the specified width. If end is specified only the sub-string up to the end is drawn.
+// White space is stripped at the beginning of the rows, the text is split at word boundaries or when new-line characters are encountered.
+// Words longer than the max width are slit at nearest character (i.e. no hyphenation).
+void nvgTextBox(NVGcontext* ctx, float x, float y, float breakRowWidth, const char* string, const char* end);
+
+// Measures the specified text string. Parameter bounds should be a pointer to float[4],
+// if the bounding box of the text should be returned. The bounds value are [xmin,ymin, xmax,ymax]
+// Returns the horizontal advance of the measured text (i.e. where the next character should drawn).
+// Measured values are returned in local coordinate space.
+float nvgTextBounds(NVGcontext* ctx, float x, float y, const char* string, const char* end, float* bounds);
+
+// Measures the specified multi-text string. Parameter bounds should be a pointer to float[4],
+// if the bounding box of the text should be returned. The bounds value are [xmin,ymin, xmax,ymax]
+// Measured values are returned in local coordinate space.
+void nvgTextBoxBounds(NVGcontext* ctx, float x, float y, float breakRowWidth, const char* string, const char* end, float* bounds);
+
+// Calculates the glyph x positions of the specified text. If end is specified only the sub-string will be used.
+// Measured values are returned in local coordinate space.
+int nvgTextGlyphPositions(NVGcontext* ctx, float x, float y, const char* string, const char* end, NVGglyphPosition* positions, int maxPositions);
+
+// Returns the vertical metrics based on the current text style.
+// Measured values are returned in local coordinate space.
+void nvgTextMetrics(NVGcontext* ctx, float* ascender, float* descender, float* lineh);
+
+// Breaks the specified text into lines. If end is specified only the sub-string will be used.
+// White space is stripped at the beginning of the rows, the text is split at word boundaries or when new-line characters are encountered.
+// Words longer than the max width are slit at nearest character (i.e. no hyphenation).
+int nvgTextBreakLines(NVGcontext* ctx, const char* string, const char* end, float breakRowWidth, NVGtextRow* rows, int maxRows);
+
+//
+// Internal Render API
+//
+enum NVGtexture {
+	NVG_TEXTURE_ALPHA = 0x01,
+	NVG_TEXTURE_RGBA = 0x02,
+};
+
+struct NVGscissor {
+	float xform[6];
+	float extent[2];
+};
+typedef struct NVGscissor NVGscissor;
+
+struct NVGvertex {
+	float x,y,u,v;
+};
+typedef struct NVGvertex NVGvertex;
+
+struct NVGpath {
+	int first;
+	int count;
+	unsigned char closed;
+	int nbevel;
+	NVGvertex* fill;
+	int nfill;
+	NVGvertex* stroke;
+	int nstroke;
+	int winding;
+	int convex;
+};
+typedef struct NVGpath NVGpath;
+
+struct NVGparams {
+	void* userPtr;
+	int edgeAntiAlias;
+	int (*renderCreate)(void* uptr);
+	int (*renderCreateTexture)(void* uptr, int type, int w, int h, int imageFlags, const unsigned char* data);
+	int (*renderDeleteTexture)(void* uptr, int image);
+	int (*renderUpdateTexture)(void* uptr, int image, int x, int y, int w, int h, const unsigned char* data);
+	int (*renderGetTextureSize)(void* uptr, int image, int* w, int* h);
+	void (*renderViewport)(void* uptr, float width, float height, float devicePixelRatio);
+	void (*renderCancel)(void* uptr);
+	void (*renderFlush)(void* uptr);
+	void (*renderFill)(void* uptr, NVGpaint* paint, NVGcompositeOperationState compositeOperation, NVGscissor* scissor, float fringe, const float* bounds, const NVGpath* paths, int npaths);
+	void (*renderStroke)(void* uptr, NVGpaint* paint, NVGcompositeOperationState compositeOperation, NVGscissor* scissor, float fringe, float strokeWidth, const NVGpath* paths, int npaths);
+	void (*renderTriangles)(void* uptr, NVGpaint* paint, NVGcompositeOperationState compositeOperation, NVGscissor* scissor, const NVGvertex* verts, int nverts, float fringe);
+	void (*renderDelete)(void* uptr);
+};
+typedef struct NVGparams NVGparams;
+
+// Constructor and destructor, called by the render back-end.
+NVGcontext* nvgCreateInternal(NVGparams* params);
+void nvgDeleteInternal(NVGcontext* ctx);
+
+NVGparams* nvgInternalParams(NVGcontext* ctx);
+
+// Debug function to dump cached path data.
+void nvgDebugDumpPathCache(NVGcontext* ctx);
+
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+#define NVG_NOTUSED(v) for (;;) { (void)(1 ? (void)0 : ( (void)(v) ) ); break; }
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // NANOVG_H

third_party/nanovg/src/nanovg_gl_utils.h

@@ -0,0 +1,154 @@
+//
+// Copyright (c) 2009-2013 Mikko Mononen [email protected]
+//
+// This software is provided 'as-is', without any express or implied
+// warranty.  In no event will the authors be held liable for any damages
+// arising from the use of this software.
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+// 1. The origin of this software must not be misrepresented; you must not
+//    claim that you wrote the original software. If you use this software
+//    in a product, an acknowledgment in the product documentation would be
+//    appreciated but is not required.
+// 2. Altered source versions must be plainly marked as such, and must not be
+//    misrepresented as being the original software.
+// 3. This notice may not be removed or altered from any source distribution.
+//
+#ifndef NANOVG_GL_UTILS_H
+#define NANOVG_GL_UTILS_H
+
+struct NVGLUframebuffer {
+	NVGcontext* ctx;
+	GLuint fbo;
+	GLuint rbo;
+	GLuint texture;
+	int image;
+};
+typedef struct NVGLUframebuffer NVGLUframebuffer;
+
+// Helper function to create GL frame buffer to render to.
+void nvgluBindFramebuffer(NVGLUframebuffer* fb);
+NVGLUframebuffer* nvgluCreateFramebuffer(NVGcontext* ctx, int w, int h, int imageFlags);
+void nvgluDeleteFramebuffer(NVGLUframebuffer* fb);
+
+#endif // NANOVG_GL_UTILS_H
+
+#ifdef NANOVG_GL_IMPLEMENTATION
+
+#if defined(NANOVG_GL3) || defined(NANOVG_GLES2) || defined(NANOVG_GLES3)
+// FBO is core in OpenGL 3>.
+#	define NANOVG_FBO_VALID 1
+#elif defined(NANOVG_GL2)
+// On OS X including glext defines FBO on GL2 too.
+#	ifdef __APPLE__
+#		include <OpenGL/glext.h>
+#		define NANOVG_FBO_VALID 1
+#	endif
+#endif
+
+static GLint defaultFBO = -1;
+
+NVGLUframebuffer* nvgluCreateFramebuffer(NVGcontext* ctx, int w, int h, int imageFlags)
+{
+#ifdef NANOVG_FBO_VALID
+	GLint defaultFBO;
+	GLint defaultRBO;
+	NVGLUframebuffer* fb = NULL;
+
+	glGetIntegerv(GL_FRAMEBUFFER_BINDING, &defaultFBO);
+	glGetIntegerv(GL_RENDERBUFFER_BINDING, &defaultRBO);
+
+	fb = (NVGLUframebuffer*)malloc(sizeof(NVGLUframebuffer));
+	if (fb == NULL) goto error;
+	memset(fb, 0, sizeof(NVGLUframebuffer));
+
+	fb->image = nvgCreateImageRGBA(ctx, w, h, imageFlags | NVG_IMAGE_FLIPY | NVG_IMAGE_PREMULTIPLIED, NULL);
+
+#if defined NANOVG_GL2
+	fb->texture = nvglImageHandleGL2(ctx, fb->image);
+#elif defined NANOVG_GL3
+	fb->texture = nvglImageHandleGL3(ctx, fb->image);
+#elif defined NANOVG_GLES2
+	fb->texture = nvglImageHandleGLES2(ctx, fb->image);
+#elif defined NANOVG_GLES3
+	fb->texture = nvglImageHandleGLES3(ctx, fb->image);
+#endif
+
+	fb->ctx = ctx;
+
+	// frame buffer object
+	glGenFramebuffers(1, &fb->fbo);
+	glBindFramebuffer(GL_FRAMEBUFFER, fb->fbo);
+
+	// render buffer object
+	glGenRenderbuffers(1, &fb->rbo);
+	glBindRenderbuffer(GL_RENDERBUFFER, fb->rbo);
+	glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, w, h);
+
+	// combine all
+	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, fb->texture, 0);
+	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, fb->rbo);
+
+	if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
+#ifdef GL_DEPTH24_STENCIL8
+		// If GL_STENCIL_INDEX8 is not supported, try GL_DEPTH24_STENCIL8 as a fallback.
+		// Some graphics cards require a depth buffer along with a stencil.
+		glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, w, h);
+		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, fb->texture, 0);
+		glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, fb->rbo);
+
+		if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+#endif // GL_DEPTH24_STENCIL8
+			goto error;
+	}
+
+	glBindFramebuffer(GL_FRAMEBUFFER, defaultFBO);
+	glBindRenderbuffer(GL_RENDERBUFFER, defaultRBO);
+	return fb;
+error:
+	glBindFramebuffer(GL_FRAMEBUFFER, defaultFBO);
+	glBindRenderbuffer(GL_RENDERBUFFER, defaultRBO);
+	nvgluDeleteFramebuffer(fb);
+	return NULL;
+#else
+	NVG_NOTUSED(ctx);
+	NVG_NOTUSED(w);
+	NVG_NOTUSED(h);
+	NVG_NOTUSED(imageFlags);
+	return NULL;
+#endif
+}
+
+void nvgluBindFramebuffer(NVGLUframebuffer* fb)
+{
+#ifdef NANOVG_FBO_VALID
+	if (defaultFBO == -1) glGetIntegerv(GL_FRAMEBUFFER_BINDING, &defaultFBO);
+	glBindFramebuffer(GL_FRAMEBUFFER, fb != NULL ? fb->fbo : defaultFBO);
+#else
+	NVG_NOTUSED(fb);
+#endif
+}
+
+void nvgluDeleteFramebuffer(NVGLUframebuffer* fb)
+{
+#ifdef NANOVG_FBO_VALID
+	if (fb == NULL) return;
+	if (fb->fbo != 0)
+		glDeleteFramebuffers(1, &fb->fbo);
+	if (fb->rbo != 0)
+		glDeleteRenderbuffers(1, &fb->rbo);
+	if (fb->image >= 0)
+		nvgDeleteImage(fb->ctx, fb->image);
+	fb->ctx = NULL;
+	fb->fbo = 0;
+	fb->rbo = 0;
+	fb->texture = 0;
+	fb->image = -1;
+	free(fb);
+#else
+	NVG_NOTUSED(fb);
+#endif
+}
+
+#endif // NANOVG_GL_IMPLEMENTATION