diff options
Diffstat (limited to 'third-party/fontstash/gl3corefontstash.h')
| -rw-r--r-- | third-party/fontstash/gl3corefontstash.h | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/third-party/fontstash/gl3corefontstash.h b/third-party/fontstash/gl3corefontstash.h new file mode 100644 index 0000000..2cd08c7 --- /dev/null +++ b/third-party/fontstash/gl3corefontstash.h @@ -0,0 +1,240 @@ +// +// Copyright (c) 2009-2013 Mikko Mononen memon@inside.org +// +// 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 GL3COREFONTSTASH_H +#define GL3COREFONTSTASH_H + +#ifdef __cplusplus +extern "C" { +#endif + +FONS_DEF FONScontext* glfonsCreate(int width, int height, int flags); +FONS_DEF void glfonsDelete(FONScontext* ctx); + +FONS_DEF unsigned int glfonsRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a); + +#ifdef __cplusplus +} +#endif + +#endif // GL3COREFONTSTASH_H + +#ifdef GLFONTSTASH_IMPLEMENTATION + +#ifndef GLFONS_VERTEX_ATTRIB +# define GLFONS_VERTEX_ATTRIB 0 +#endif + +#ifndef GLFONS_TCOORD_ATTRIB +# define GLFONS_TCOORD_ATTRIB 1 +#endif + +#ifndef GLFONS_COLOR_ATTRIB +# define GLFONS_COLOR_ATTRIB 2 +#endif + +struct GLFONScontext { + GLuint tex; + int width, height; + GLuint vertexArray; + GLuint vertexBuffer; + GLuint tcoordBuffer; + GLuint colorBuffer; +}; +typedef struct GLFONScontext GLFONScontext; + +static int glfons__renderCreate(void* userPtr, int width, int height) +{ + GLFONScontext* gl = (GLFONScontext*)userPtr; + + // Create may be called multiple times, delete existing texture. + if (gl->tex != 0) { + glDeleteTextures(1, &gl->tex); + gl->tex = 0; + } + + glGenTextures(1, &gl->tex); + if (!gl->tex) return 0; + + if (!gl->vertexArray) glGenVertexArrays(1, &gl->vertexArray); + if (!gl->vertexArray) return 0; + + glBindVertexArray(gl->vertexArray); + + if (!gl->vertexBuffer) glGenBuffers(1, &gl->vertexBuffer); + if (!gl->vertexBuffer) return 0; + + if (!gl->tcoordBuffer) glGenBuffers(1, &gl->tcoordBuffer); + if (!gl->tcoordBuffer) return 0; + + if (!gl->colorBuffer) glGenBuffers(1, &gl->colorBuffer); + if (!gl->colorBuffer) return 0; + + gl->width = width; + gl->height = height; + glBindTexture(GL_TEXTURE_2D, gl->tex); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, gl->width, gl->height, 0, GL_RED, GL_UNSIGNED_BYTE, NULL); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + static GLint swizzleRgbaParams[4] = {GL_ONE, GL_ONE, GL_ONE, GL_RED}; + glTexParameteriv(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_RGBA, swizzleRgbaParams); + + return 1; +} + +static int glfons__renderResize(void* userPtr, int width, int height) +{ + // Reuse create to resize too. + return glfons__renderCreate(userPtr, width, height); +} + +static void glfons__renderUpdate(void* userPtr, int* rect, const unsigned char* data) +{ + GLFONScontext* gl = (GLFONScontext*)userPtr; + int w = rect[2] - rect[0]; + int h = rect[3] - rect[1]; + + if (gl->tex == 0) return; + + // Push old values + GLint alignment, rowLength, skipPixels, skipRows; + glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment); + glGetIntegerv(GL_UNPACK_ROW_LENGTH, &rowLength); + glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &skipPixels); + glGetIntegerv(GL_UNPACK_SKIP_ROWS, &skipRows); + + glBindTexture(GL_TEXTURE_2D, gl->tex); + + glPixelStorei(GL_UNPACK_ALIGNMENT, 1); + glPixelStorei(GL_UNPACK_ROW_LENGTH, gl->width); + glPixelStorei(GL_UNPACK_SKIP_PIXELS, rect[0]); + glPixelStorei(GL_UNPACK_SKIP_ROWS, rect[1]); + + glTexSubImage2D(GL_TEXTURE_2D, 0, rect[0], rect[1], w, h, GL_RED, GL_UNSIGNED_BYTE, data); + + // Pop old values + glPixelStorei(GL_UNPACK_ALIGNMENT, alignment); + glPixelStorei(GL_UNPACK_ROW_LENGTH, rowLength); + glPixelStorei(GL_UNPACK_SKIP_PIXELS, skipPixels); + glPixelStorei(GL_UNPACK_SKIP_ROWS, skipRows); +} + +static void glfons__renderDraw(void* userPtr, const float* verts, const float* tcoords, const unsigned int* colors, int nverts) +{ + GLFONScontext* gl = (GLFONScontext*)userPtr; + if (gl->tex == 0 || gl->vertexArray == 0) return; + + glActiveTexture(GL_TEXTURE0); + glBindTexture(GL_TEXTURE_2D, gl->tex); + + glBindVertexArray(gl->vertexArray); + + glEnableVertexAttribArray(GLFONS_VERTEX_ATTRIB); + glBindBuffer(GL_ARRAY_BUFFER, gl->vertexBuffer); + glBufferData(GL_ARRAY_BUFFER, nverts * 2 * sizeof(float), verts, GL_DYNAMIC_DRAW); + glVertexAttribPointer(GLFONS_VERTEX_ATTRIB, 2, GL_FLOAT, GL_FALSE, 0, NULL); + + glEnableVertexAttribArray(GLFONS_TCOORD_ATTRIB); + glBindBuffer(GL_ARRAY_BUFFER, gl->tcoordBuffer); + glBufferData(GL_ARRAY_BUFFER, nverts * 2 * sizeof(float), tcoords, GL_DYNAMIC_DRAW); + glVertexAttribPointer(GLFONS_TCOORD_ATTRIB, 2, GL_FLOAT, GL_FALSE, 0, NULL); + + glEnableVertexAttribArray(GLFONS_COLOR_ATTRIB); + glBindBuffer(GL_ARRAY_BUFFER, gl->colorBuffer); + glBufferData(GL_ARRAY_BUFFER, nverts * sizeof(unsigned int), colors, GL_DYNAMIC_DRAW); + glVertexAttribPointer(GLFONS_COLOR_ATTRIB, 4, GL_UNSIGNED_BYTE, GL_FALSE, 0, NULL); + + glDrawArrays(GL_TRIANGLES, 0, nverts); + + glDisableVertexAttribArray(GLFONS_VERTEX_ATTRIB); + glDisableVertexAttribArray(GLFONS_TCOORD_ATTRIB); + glDisableVertexAttribArray(GLFONS_COLOR_ATTRIB); + + glBindVertexArray(0); +} + +static void glfons__renderDelete(void* userPtr) +{ + GLFONScontext* gl = (GLFONScontext*)userPtr; + if (gl->tex != 0) { + glDeleteTextures(1, &gl->tex); + gl->tex = 0; + } + + glBindVertexArray(0); + + if (gl->vertexBuffer != 0) { + glDeleteBuffers(1, &gl->vertexBuffer); + gl->vertexBuffer = 0; + } + + if (gl->tcoordBuffer != 0) { + glDeleteBuffers(1, &gl->tcoordBuffer); + gl->tcoordBuffer = 0; + } + + if (gl->colorBuffer != 0) { + glDeleteBuffers(1, &gl->colorBuffer); + gl->colorBuffer = 0; + } + + if (gl->vertexArray != 0) { + glDeleteVertexArrays(1, &gl->vertexArray); + gl->vertexArray = 0; + } + + free(gl); +} + +FONS_DEF FONScontext* glfonsCreate(int width, int height, int flags) +{ + FONSparams params; + GLFONScontext* gl; + + gl = (GLFONScontext*)malloc(sizeof(GLFONScontext)); + if (gl == NULL) goto error; + memset(gl, 0, sizeof(GLFONScontext)); + + memset(¶ms, 0, sizeof(params)); + params.width = width; + params.height = height; + params.flags = (unsigned char)flags; + params.renderCreate = glfons__renderCreate; + params.renderResize = glfons__renderResize; + params.renderUpdate = glfons__renderUpdate; + params.renderDraw = glfons__renderDraw; + params.renderDelete = glfons__renderDelete; + params.userPtr = gl; + + return fonsCreateInternal(¶ms); + +error: + if (gl != NULL) free(gl); + return NULL; +} + +FONS_DEF void glfonsDelete(FONScontext* ctx) +{ + fonsDeleteInternal(ctx); +} + +FONS_DEF unsigned int glfonsRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + return (r) | (g << 8) | (b << 16) | (a << 24); +} + +#endif // GLFONTSTASH_IMPLEMENTATION |