/*

SDL - Simple DirectMedia Layer

Copyright (C) 1997-2011 Sam Lantinga

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public

License as published by the Free Software Foundation; either

version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public

License along with this library; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Sam Lantinga

slouken@libsdl.org

*/

#include "SDL_config.h"

#if SDL_VIDEO_RENDER_OGL && !SDL_RENDER_DISABLED

#include "SDL_hints.h"

#include "SDL_log.h"

#include "SDL_opengl.h"

#include "../SDL_sysrender.h"

#include "SDL_shaders_gl.h"

#ifdef __MACOSX__

#include <OpenGL/OpenGL.h>

#endif

/* OpenGL renderer implementation */

/* Details on optimizing the texture path on Mac OS X:

http://developer.apple.com/library/mac/#documentation/GraphicsImaging/Conceptual/OpenGL-MacProgGuide/opengl_texturedata/opengl_texturedata.html

*/

/* Used to re-create the window with OpenGL capability */

extern int SDL_RecreateWindow(SDL_Window * window, Uint32 flags);

static const float inv255f = 1.0f / 255.0f;

static SDL_Renderer *GL_CreateRenderer(SDL_Window * window, Uint32 flags);

static void GL_WindowEvent(SDL_Renderer * renderer,

const SDL_WindowEvent *event);

static int GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture);

static int GL_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,

const SDL_Rect * rect, const void *pixels,

int pitch);

static int GL_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,

const SDL_Rect * rect, void **pixels, int *pitch);

static void GL_UnlockTexture(SDL_Renderer * renderer, SDL_Texture * texture);

static void GL_SetClipRect(SDL_Renderer * renderer, const SDL_Rect * rect);

static int GL_RenderClear(SDL_Renderer * renderer);

static int GL_RenderDrawPoints(SDL_Renderer * renderer,

const SDL_Point * points, int count);

static int GL_RenderDrawLines(SDL_Renderer * renderer,

const SDL_Point * points, int count);

static int GL_RenderFillRects(SDL_Renderer * renderer,

const SDL_Rect ** rects, int count);

static int GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,

const SDL_Rect * srcrect, const SDL_Rect * dstrect);

static int GL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,

Uint32 pixel_format, void * pixels, int pitch);

static void GL_RenderPresent(SDL_Renderer * renderer);

static void GL_DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture);

static void GL_DestroyRenderer(SDL_Renderer * renderer);

SDL_RenderDriver GL_RenderDriver = {

GL_CreateRenderer,

{

"opengl",

(SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC),

1,

{SDL_PIXELFORMAT_ARGB8888},

0,

0}

};

typedef struct

{

SDL_GLContext context;

SDL_bool updateSize;

SDL_bool GL_ARB_texture_rectangle_supported;

int blendMode;

/* OpenGL functions */

#define SDL_PROC(ret,func,params) ret (APIENTRY *func) params;

#include "SDL_glfuncs.h"

#undef SDL_PROC

void (*glTextureRangeAPPLE) (GLenum target, GLsizei length,

const GLvoid * pointer);

/* Multitexture support */

SDL_bool GL_ARB_multitexture_supported;

PFNGLACTIVETEXTUREARBPROC glActiveTextureARB;

int num_texture_units;

/* Shader support */

GL_ShaderContext *shaders;

} GL_RenderData;

typedef struct

{

GLuint texture;

GLenum type;

GLfloat texw;

GLfloat texh;

GLenum format;

GLenum formattype;

void *pixels;

int pitch;

SDL_Rect locked_rect;

/* YV12 texture support */

SDL_bool yuv;

GLuint utexture;

GLuint vtexture;

} GL_TextureData;

static void

GL_SetError(const char *prefix, GLenum result)

{

const char *error;

switch (result) {

case GL_NO_ERROR:

error = "GL_NO_ERROR";

break;

case GL_INVALID_ENUM:

error = "GL_INVALID_ENUM";

break;

case GL_INVALID_VALUE:

error = "GL_INVALID_VALUE";

break;

case GL_INVALID_OPERATION:

error = "GL_INVALID_OPERATION";

break;

case GL_STACK_OVERFLOW:

error = "GL_STACK_OVERFLOW";

break;

case GL_STACK_UNDERFLOW:

error = "GL_STACK_UNDERFLOW";

break;

case GL_OUT_OF_MEMORY:

error = "GL_OUT_OF_MEMORY";

break;

case GL_TABLE_TOO_LARGE:

error = "GL_TABLE_TOO_LARGE";

break;

default:

error = "UNKNOWN";

break;

}

SDL_SetError("%s: %s", prefix, error);

}

static int

GL_LoadFunctions(GL_RenderData * data)

{

#ifdef __SDL_NOGETPROCADDR__

#define SDL_PROC(ret,func,params) data->func=func;

#else

#define SDL_PROC(ret,func,params) \

do { \

data->func = SDL_GL_GetProcAddress(#func); \

if ( ! data->func ) { \

SDL_SetError("Couldn't load GL function %s: %s\n", #func, SDL_GetError()); \

return -1; \

} \

} while ( 0 );

#endif /* __SDL_NOGETPROCADDR__ */

#include "SDL_glfuncs.h"

#undef SDL_PROC

return 0;

}

SDL_Renderer *

GL_CreateRenderer(SDL_Window * window, Uint32 flags)

{

SDL_Renderer *renderer;

GL_RenderData *data;

const char *hint;

GLint value;

Uint32 window_flags;

window_flags = SDL_GetWindowFlags(window);

if (!(window_flags & SDL_WINDOW_OPENGL)) {

if (SDL_RecreateWindow(window, window_flags | SDL_WINDOW_OPENGL) < 0) {

return NULL;

}

}

renderer = (SDL_Renderer *) SDL_calloc(1, sizeof(*renderer));

if (!renderer) {

SDL_OutOfMemory();

return NULL;

}

data = (GL_RenderData *) SDL_calloc(1, sizeof(*data));

if (!data) {

GL_DestroyRenderer(renderer);

SDL_OutOfMemory();

return NULL;

}

renderer->WindowEvent = GL_WindowEvent;

renderer->CreateTexture = GL_CreateTexture;

renderer->UpdateTexture = GL_UpdateTexture;

renderer->LockTexture = GL_LockTexture;

renderer->UnlockTexture = GL_UnlockTexture;

renderer->SetClipRect = GL_SetClipRect;

renderer->RenderClear = GL_RenderClear;

renderer->RenderDrawPoints = GL_RenderDrawPoints;

renderer->RenderDrawLines = GL_RenderDrawLines;

renderer->RenderFillRects = GL_RenderFillRects;

renderer->RenderCopy = GL_RenderCopy;

renderer->RenderReadPixels = GL_RenderReadPixels;

renderer->RenderPresent = GL_RenderPresent;

renderer->DestroyTexture = GL_DestroyTexture;

renderer->DestroyRenderer = GL_DestroyRenderer;

renderer->info = GL_RenderDriver.info;

renderer->driverdata = data;

renderer->info.flags = SDL_RENDERER_ACCELERATED;

data->context = SDL_GL_CreateContext(window);

if (!data->context) {

GL_DestroyRenderer(renderer);

return NULL;

}

if (SDL_GL_MakeCurrent(window, data->context) < 0) {

GL_DestroyRenderer(renderer);

return NULL;

}

if (GL_LoadFunctions(data) < 0) {

GL_DestroyRenderer(renderer);

return NULL;

}

#ifdef __MACOSX__

/* Enable multi-threaded rendering */

/* Disabled until Ryan finishes his VBO/PBO code...

CGLEnable(CGLGetCurrentContext(), kCGLCEMPEngine);

*/

#endif

if (flags & SDL_RENDERER_PRESENTVSYNC) {

SDL_GL_SetSwapInterval(1);

} else {

SDL_GL_SetSwapInterval(0);

}

if (SDL_GL_GetSwapInterval() > 0) {

renderer->info.flags |= SDL_RENDERER_PRESENTVSYNC;

}

data->glGetIntegerv(GL_MAX_TEXTURE_SIZE, &value);

renderer->info.max_texture_width = value;

data->glGetIntegerv(GL_MAX_TEXTURE_SIZE, &value);

renderer->info.max_texture_height = value;

if (SDL_GL_ExtensionSupported("GL_ARB_texture_rectangle")

|| SDL_GL_ExtensionSupported("GL_EXT_texture_rectangle")) {

data->GL_ARB_texture_rectangle_supported = SDL_TRUE;

}

if (SDL_GL_ExtensionSupported("GL_APPLE_texture_range")) {

data->glTextureRangeAPPLE =

(void (*)(GLenum, GLsizei, const GLvoid *))

SDL_GL_GetProcAddress("glTextureRangeAPPLE");

}

/* Check for multitexture support */

if (SDL_GL_ExtensionSupported("GL_ARB_multitexture")) {

data->glActiveTextureARB = (PFNGLACTIVETEXTUREARBPROC) SDL_GL_GetProcAddress("glActiveTextureARB");

if (data->glActiveTextureARB) {

data->GL_ARB_multitexture_supported = SDL_TRUE;

data->glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &data->num_texture_units);

}

}

/* Check for shader support */

hint = SDL_GetHint(SDL_HINT_RENDER_OPENGL_SHADERS);

if (!hint || *hint != '0') {

data->shaders = GL_CreateShaderContext();

}

SDL_LogInfo(SDL_LOG_CATEGORY_RENDER, "OpenGL shaders: %s",

data->shaders ? "ENABLED" : "DISABLED");

/* We support YV12 textures using 3 textures and a shader */

if (data->shaders && data->num_texture_units >= 3) {

renderer->info.texture_formats[renderer->info.num_texture_formats++] = SDL_PIXELFORMAT_YV12;

renderer->info.texture_formats[renderer->info.num_texture_formats++] = SDL_PIXELFORMAT_IYUV;

}

/* Set up parameters for rendering */

data->blendMode = -1;

data->glDisable(GL_DEPTH_TEST);

data->glDisable(GL_CULL_FACE);

/* This ended up causing video discrepancies between OpenGL and Direct3D */

/*data->glEnable(GL_LINE_SMOOTH);*/

data->updateSize = SDL_TRUE;

return renderer;

}

static SDL_GLContext SDL_CurrentContext = NULL;

static int

GL_ActivateRenderer(SDL_Renderer * renderer)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

SDL_Window *window = renderer->window;

if (SDL_CurrentContext != data->context) {

if (SDL_GL_MakeCurrent(window, data->context) < 0) {

return -1;

}

SDL_CurrentContext = data->context;

}

if (data->updateSize) {

int w, h;

SDL_GetWindowSize(window, &w, &h);

data->glMatrixMode(GL_PROJECTION);

data->glLoadIdentity();

data->glMatrixMode(GL_MODELVIEW);

data->glLoadIdentity();

data->glViewport(0, 0, w, h);

data->glOrtho(0.0, (GLdouble) w, (GLdouble) h, 0.0, 0.0, 1.0);

data->updateSize = SDL_FALSE;

}

return 0;

}

static void

GL_WindowEvent(SDL_Renderer * renderer, const SDL_WindowEvent *event)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

if (event->event == SDL_WINDOWEVENT_RESIZED) {

/* Rebind the context to the window area and update matrices */

SDL_CurrentContext = NULL;

data->updateSize = SDL_TRUE;

}

}

static __inline__ int

power_of_2(int input)

{

int value = 1;

while (value < input) {

value <<= 1;

}

return value;

}

static __inline__ SDL_bool

convert_format(GL_RenderData *renderdata, Uint32 pixel_format,

GLint* internalFormat, GLenum* format, GLenum* type)

{

switch (pixel_format) {

case SDL_PIXELFORMAT_ARGB8888:

*internalFormat = GL_RGBA8;

*format = GL_BGRA;

*type = GL_UNSIGNED_INT_8_8_8_8_REV;

break;

case SDL_PIXELFORMAT_YV12:

case SDL_PIXELFORMAT_IYUV:

*internalFormat = GL_LUMINANCE;

*format = GL_LUMINANCE;

*type = GL_UNSIGNED_BYTE;

break;

default:

return SDL_FALSE;

}

return SDL_TRUE;

}

static int

GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)

{

GL_RenderData *renderdata = (GL_RenderData *) renderer->driverdata;

GL_TextureData *data;

GLint internalFormat;

GLenum format, type;

int texture_w, texture_h;

GLenum result;

GL_ActivateRenderer(renderer);

if (!convert_format(renderdata, texture->format, &internalFormat,

&format, &type)) {

SDL_SetError("Texture format %s not supported by OpenGL",

SDL_GetPixelFormatName(texture->format));

return -1;

}

data = (GL_TextureData *) SDL_calloc(1, sizeof(*data));

if (!data) {

SDL_OutOfMemory();

return -1;

}

if (texture->access == SDL_TEXTUREACCESS_STREAMING) {

size_t size;

data->pitch = texture->w * SDL_BYTESPERPIXEL(texture->format);

size = texture->h * data->pitch;

if (texture->format == SDL_PIXELFORMAT_YV12 ||

texture->format == SDL_PIXELFORMAT_IYUV) {

/* Need to add size for the U and V planes */

size += (2 * (texture->h * data->pitch) / 4);

}

data->pixels = SDL_malloc(size);

if (!data->pixels) {

SDL_OutOfMemory();

SDL_free(data);

return -1;

}

}

texture->driverdata = data;

renderdata->glGetError();

renderdata->glGenTextures(1, &data->texture);

if (renderdata->GL_ARB_texture_rectangle_supported) {

data->type = GL_TEXTURE_RECTANGLE_ARB;

texture_w = texture->w;

texture_h = texture->h;

data->texw = (GLfloat) texture_w;

data->texh = (GLfloat) texture_h;

} else {

data->type = GL_TEXTURE_2D;

texture_w = power_of_2(texture->w);

texture_h = power_of_2(texture->h);

data->texw = (GLfloat) (texture->w) / texture_w;

data->texh = (GLfloat) texture->h / texture_h;

}

data->format = format;

data->formattype = type;

renderdata->glEnable(data->type);

renderdata->glBindTexture(data->type, data->texture);

renderdata->glTexParameteri(data->type, GL_TEXTURE_MIN_FILTER,

GL_LINEAR);

renderdata->glTexParameteri(data->type, GL_TEXTURE_MAG_FILTER,

GL_LINEAR);

renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_S,

GL_CLAMP_TO_EDGE);

renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_T,

GL_CLAMP_TO_EDGE);

#ifdef __MACOSX__

#ifndef GL_TEXTURE_STORAGE_HINT_APPLE

#define GL_TEXTURE_STORAGE_HINT_APPLE 0x85BC

#endif

#ifndef STORAGE_CACHED_APPLE

#define STORAGE_CACHED_APPLE 0x85BE

#endif

#ifndef STORAGE_SHARED_APPLE

#define STORAGE_SHARED_APPLE 0x85BF

#endif

if (texture->access == SDL_TEXTUREACCESS_STREAMING) {

renderdata->glTexParameteri(data->type, GL_TEXTURE_STORAGE_HINT_APPLE,

GL_STORAGE_SHARED_APPLE);

} else {

renderdata->glTexParameteri(data->type, GL_TEXTURE_STORAGE_HINT_APPLE,

GL_STORAGE_CACHED_APPLE);

}

if (texture->access == SDL_TEXTUREACCESS_STREAMING

&& texture->format == SDL_PIXELFORMAT_ARGB8888) {

renderdata->glPixelStorei(GL_UNPACK_CLIENT_STORAGE_APPLE, GL_TRUE);

renderdata->glTexImage2D(data->type, 0, internalFormat, texture_w,

texture_h, 0, format, type, data->pixels);

}

else

#endif

{

renderdata->glTexImage2D(data->type, 0, internalFormat, texture_w,

texture_h, 0, format, type, NULL);

}

renderdata->glDisable(data->type);

result = renderdata->glGetError();

if (result != GL_NO_ERROR) {

GL_SetError("glTexImage2D()", result);

return -1;

}

if (texture->format == SDL_PIXELFORMAT_YV12 ||

texture->format == SDL_PIXELFORMAT_IYUV) {

data->yuv = SDL_TRUE;

renderdata->glGenTextures(1, &data->utexture);

renderdata->glGenTextures(1, &data->vtexture);

renderdata->glEnable(data->type);

renderdata->glBindTexture(data->type, data->utexture);

renderdata->glTexParameteri(data->type, GL_TEXTURE_MIN_FILTER,

GL_LINEAR);

renderdata->glTexParameteri(data->type, GL_TEXTURE_MAG_FILTER,

GL_LINEAR);

renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_S,

GL_CLAMP_TO_EDGE);

renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_T,

GL_CLAMP_TO_EDGE);

renderdata->glTexImage2D(data->type, 0, internalFormat, texture_w/2,

texture_h/2, 0, format, type, NULL);

renderdata->glBindTexture(data->type, data->vtexture);

renderdata->glTexParameteri(data->type, GL_TEXTURE_MIN_FILTER,

GL_LINEAR);

renderdata->glTexParameteri(data->type, GL_TEXTURE_MAG_FILTER,

GL_LINEAR);

renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_S,

GL_CLAMP_TO_EDGE);

renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_T,

GL_CLAMP_TO_EDGE);

renderdata->glTexImage2D(data->type, 0, internalFormat, texture_w/2,

texture_h/2, 0, format, type, NULL);

renderdata->glDisable(data->type);

}

return 0;

}

static int

GL_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,

const SDL_Rect * rect, const void *pixels, int pitch)

{

GL_RenderData *renderdata = (GL_RenderData *) renderer->driverdata;

GL_TextureData *data = (GL_TextureData *) texture->driverdata;

GLenum result;

GL_ActivateRenderer(renderer);

renderdata->glGetError();

renderdata->glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

renderdata->glPixelStorei(GL_UNPACK_ROW_LENGTH,

(pitch / SDL_BYTESPERPIXEL(texture->format)));

renderdata->glEnable(data->type);

renderdata->glBindTexture(data->type, data->texture);

renderdata->glTexSubImage2D(data->type, 0, rect->x, rect->y, rect->w,

rect->h, data->format, data->formattype,

pixels);

if (data->yuv) {

/* Skip to the top of the next texture */

const void *top = (const void*)((const Uint8*)pixels + (texture->h-rect->y) * pitch - rect->x);

/* Skip to the correct offset into the next texture */

pixels = (const void*)((const Uint8*)top + (rect->y / 2) * pitch + rect->x / 2);

if (texture->format == SDL_PIXELFORMAT_YV12) {

renderdata->glBindTexture(data->type, data->vtexture);

} else {

renderdata->glBindTexture(data->type, data->utexture);

}

renderdata->glTexSubImage2D(data->type, 0, rect->x/2, rect->y/2,

rect->w/2, rect->h/2,

data->format, data->formattype, pixels);

/* Skip to the top of the next texture */

top = (const void*)((const Uint8*)top + (texture->h * pitch)/4);

/* Skip to the correct offset into the next texture */

pixels = (const void*)((const Uint8*)top + (rect->y / 2) * pitch + rect->x / 2);

if (texture->format == SDL_PIXELFORMAT_YV12) {

renderdata->glBindTexture(data->type, data->utexture);

} else {

renderdata->glBindTexture(data->type, data->vtexture);

}

renderdata->glTexSubImage2D(data->type, 0, rect->x/2, rect->y/2,

rect->w/2, rect->h/2,

data->format, data->formattype, pixels);

}

renderdata->glDisable(data->type);

result = renderdata->glGetError();

if (result != GL_NO_ERROR) {

GL_SetError("glTexSubImage2D()", result);

return -1;

}

return 0;

}

static int

GL_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,

const SDL_Rect * rect, void **pixels, int *pitch)

{

GL_TextureData *data = (GL_TextureData *) texture->driverdata;

data->locked_rect = *rect;

*pixels =

(void *) ((Uint8 *) data->pixels + rect->y * data->pitch +

rect->x * SDL_BYTESPERPIXEL(texture->format));

*pitch = data->pitch;

return 0;

}

static void

GL_UnlockTexture(SDL_Renderer * renderer, SDL_Texture * texture)

{

GL_TextureData *data = (GL_TextureData *) texture->driverdata;

const SDL_Rect *rect;

void *pixels;

rect = &data->locked_rect;

pixels =

(void *) ((Uint8 *) data->pixels + rect->y * data->pitch +

rect->x * SDL_BYTESPERPIXEL(texture->format));

GL_UpdateTexture(renderer, texture, rect, pixels, data->pitch);

}

static void

GL_SetClipRect(SDL_Renderer * renderer, const SDL_Rect * rect)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

GL_ActivateRenderer(renderer);

if (rect) {

int w, h;

SDL_GetWindowSize(renderer->window, &w, &h);

data->glScissor(rect->x, (h-(rect->y+rect->h)), rect->w, rect->h);

data->glEnable(GL_SCISSOR_TEST);

} else {

data->glDisable(GL_SCISSOR_TEST);

}

}

static void

GL_SetBlendMode(GL_RenderData * data, int blendMode)

{

if (blendMode != data->blendMode) {

switch (blendMode) {

case SDL_BLENDMODE_NONE:

data->glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

data->glDisable(GL_BLEND);

break;

case SDL_BLENDMODE_BLEND:

data->glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

data->glEnable(GL_BLEND);

data->glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

break;

case SDL_BLENDMODE_ADD:

data->glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

data->glEnable(GL_BLEND);

data->glBlendFunc(GL_SRC_ALPHA, GL_ONE);

break;

case SDL_BLENDMODE_MOD:

data->glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

data->glEnable(GL_BLEND);

data->glBlendFunc(GL_ZERO, GL_SRC_COLOR);

break;

}

data->blendMode = blendMode;

}

}

static int

GL_RenderClear(SDL_Renderer * renderer)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

GL_ActivateRenderer(renderer);

data->glClearColor((GLfloat) renderer->r * inv255f,

(GLfloat) renderer->g * inv255f,

(GLfloat) renderer->b * inv255f,

(GLfloat) renderer->a * inv255f);

data->glClear(GL_COLOR_BUFFER_BIT);

return 0;

}

static int

GL_RenderDrawPoints(SDL_Renderer * renderer, const SDL_Point * points,

int count)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

int i;

GL_ActivateRenderer(renderer);

GL_SetBlendMode(data, renderer->blendMode);

GL_SelectShader(data->shaders, SHADER_SOLID);

data->glColor4f((GLfloat) renderer->r * inv255f,

(GLfloat) renderer->g * inv255f,

(GLfloat) renderer->b * inv255f,

(GLfloat) renderer->a * inv255f);

data->glBegin(GL_POINTS);

for (i = 0; i < count; ++i) {

data->glVertex2f(0.5f + points[i].x, 0.5f + points[i].y);

}

data->glEnd();

return 0;

}

static int

GL_RenderDrawLines(SDL_Renderer * renderer, const SDL_Point * points,

int count)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

int i;

GL_ActivateRenderer(renderer);

GL_SetBlendMode(data, renderer->blendMode);

GL_SelectShader(data->shaders, SHADER_SOLID);

data->glColor4f((GLfloat) renderer->r * inv255f,

(GLfloat) renderer->g * inv255f,

(GLfloat) renderer->b * inv255f,

(GLfloat) renderer->a * inv255f);

if (count > 2 &&

points[0].x == points[count-1].x && points[0].y == points[count-1].y) {

data->glBegin(GL_LINE_LOOP);

/* GL_LINE_LOOP takes care of the final segment */

--count;

for (i = 0; i < count; ++i) {

data->glVertex2f(0.5f + points[i].x, 0.5f + points[i].y);

}

data->glEnd();

} else {

#if defined(__APPLE__) || defined(__WIN32__)

#else

int x1, y1, x2, y2;

#endif

data->glBegin(GL_LINE_STRIP);

for (i = 0; i < count; ++i) {

data->glVertex2f(0.5f + points[i].x, 0.5f + points[i].y);

}

data->glEnd();

/* The line is half open, so we need one more point to complete it.

* http://www.opengl.org/documentation/specs/version1.1/glspec1.1/node47.html

* If we have to, we can use vertical line and horizontal line textures

* for vertical and horizontal lines, and then create custom textures

* for diagonal lines and software render those. It's terrible, but at

* least it would be pixel perfect.

*/

data->glBegin(GL_POINTS);

#if defined(__APPLE__) || defined(__WIN32__)

/* Mac OS X and Windows seem to always leave the second point open */

data->glVertex2f(0.5f + points[count-1].x, 0.5f + points[count-1].y);

#else

/* Linux seems to leave the right-most or bottom-most point open */

x1 = points[0].x;

y1 = points[0].y;

x2 = points[count-1].x;

y2 = points[count-1].y;

if (x1 > x2) {

data->glVertex2f(0.5f + x1, 0.5f + y1);

} else if (x2 > x1) {

data->glVertex2f(0.5f + x2, 0.5f + y2);

} else if (y1 > y2) {

data->glVertex2f(0.5f + x1, 0.5f + y1);

} else if (y2 > y1) {

data->glVertex2f(0.5f + x2, 0.5f + y2);

}

#endif

data->glEnd();

}

return 0;

}

static int

GL_RenderFillRects(SDL_Renderer * renderer, const SDL_Rect ** rects, int count)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

int i;

GL_ActivateRenderer(renderer);

GL_SetBlendMode(data, renderer->blendMode);

GL_SelectShader(data->shaders, SHADER_SOLID);

data->glColor4f((GLfloat) renderer->r * inv255f,

(GLfloat) renderer->g * inv255f,

(GLfloat) renderer->b * inv255f,

(GLfloat) renderer->a * inv255f);

for (i = 0; i < count; ++i) {

const SDL_Rect *rect = rects[i];

data->glRecti(rect->x, rect->y, rect->x + rect->w, rect->y + rect->h);

}

return 0;

}

static int

GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,

const SDL_Rect * srcrect, const SDL_Rect * dstrect)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

GL_TextureData *texturedata = (GL_TextureData *) texture->driverdata;

int minx, miny, maxx, maxy;

GLfloat minu, maxu, minv, maxv;

GL_ActivateRenderer(renderer);

minx = dstrect->x;

miny = dstrect->y;

maxx = dstrect->x + dstrect->w;

maxy = dstrect->y + dstrect->h;

minu = (GLfloat) srcrect->x / texture->w;

minu *= texturedata->texw;

maxu = (GLfloat) (srcrect->x + srcrect->w) / texture->w;

maxu *= texturedata->texw;

minv = (GLfloat) srcrect->y / texture->h;

minv *= texturedata->texh;

maxv = (GLfloat) (srcrect->y + srcrect->h) / texture->h;

maxv *= texturedata->texh;

data->glEnable(texturedata->type);

if (texturedata->yuv) {

data->glActiveTextureARB(GL_TEXTURE2_ARB);

data->glBindTexture(texturedata->type, texturedata->vtexture);

data->glActiveTextureARB(GL_TEXTURE1_ARB);

data->glBindTexture(texturedata->type, texturedata->utexture);

data->glActiveTextureARB(GL_TEXTURE0_ARB);

}

data->glBindTexture(texturedata->type, texturedata->texture);

if (texture->modMode) {

data->glColor4f((GLfloat) texture->r * inv255f,

(GLfloat) texture->g * inv255f,

(GLfloat) texture->b * inv255f,

(GLfloat) texture->a * inv255f);

} else {

data->glColor4f(1.0f, 1.0f, 1.0f, 1.0f);

}

GL_SetBlendMode(data, texture->blendMode);

if (texturedata->yuv) {

GL_SelectShader(data->shaders, SHADER_YV12);

} else {

GL_SelectShader(data->shaders, SHADER_RGB);

}

data->glBegin(GL_TRIANGLE_STRIP);

data->glTexCoord2f(minu, minv);

data->glVertex2f((GLfloat) minx, (GLfloat) miny);

data->glTexCoord2f(maxu, minv);

data->glVertex2f((GLfloat) maxx, (GLfloat) miny);

data->glTexCoord2f(minu, maxv);

data->glVertex2f((GLfloat) minx, (GLfloat) maxy);

data->glTexCoord2f(maxu, maxv);

data->glVertex2f((GLfloat) maxx, (GLfloat) maxy);

data->glEnd();

data->glDisable(texturedata->type);

return 0;

}

static int

GL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,

Uint32 pixel_format, void * pixels, int pitch)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

SDL_Window *window = renderer->window;

GLint internalFormat;

GLenum format, type;

Uint8 *src, *dst, *tmp;

int w, h, length, rows;

GL_ActivateRenderer(renderer);

if (!convert_format(data, pixel_format, &internalFormat, &format, &type)) {

/* FIXME: Do a temp copy to a format that is supported */

SDL_SetError("Unsupported pixel format");

return -1;

}

SDL_GetWindowSize(window, &w, &h);

data->glPixelStorei(GL_PACK_ALIGNMENT, 1);

data->glPixelStorei(GL_PACK_ROW_LENGTH,

(pitch / SDL_BYTESPERPIXEL(pixel_format)));

data->glReadPixels(rect->x, (h-rect->y)-rect->h, rect->w, rect->h,

format, type, pixels);

/* Flip the rows to be top-down */

length = rect->w * SDL_BYTESPERPIXEL(pixel_format);

src = (Uint8*)pixels + (rect->h-1)*pitch;

dst = (Uint8*)pixels;

tmp = SDL_stack_alloc(Uint8, length);

rows = rect->h / 2;

while (rows--) {

SDL_memcpy(tmp, dst, length);

SDL_memcpy(dst, src, length);

SDL_memcpy(src, tmp, length);

dst += pitch;

src -= pitch;

}

SDL_stack_free(tmp);

return 0;

}

static void

GL_RenderPresent(SDL_Renderer * renderer)

{

GL_ActivateRenderer(renderer);

SDL_GL_SwapWindow(renderer->window);

}

static void

GL_DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture)

{

GL_RenderData *renderdata = (GL_RenderData *) renderer->driverdata;

GL_TextureData *data = (GL_TextureData *) texture->driverdata;

GL_ActivateRenderer(renderer);

if (!data) {

return;

}

if (data->texture) {

renderdata->glDeleteTextures(1, &data->texture);

}

if (data->yuv) {

renderdata->glDeleteTextures(1, &data->utexture);

renderdata->glDeleteTextures(1, &data->vtexture);

}

if (data->pixels) {

SDL_free(data->pixels);

}

SDL_free(data);

texture->driverdata = NULL;

}

static void

GL_DestroyRenderer(SDL_Renderer * renderer)

{

GL_RenderData *data = (GL_RenderData *) renderer->driverdata;

if (data) {

if (data->context) {

/* SDL_GL_MakeCurrent(0, NULL); *//* doesn't do anything */

SDL_GL_DeleteContext(data->context);

}

SDL_free(data);

}

SDL_free(renderer);

}

#endif /* SDL_VIDEO_RENDER_OGL && !SDL_RENDER_DISABLED */

/* vi: set ts=4 sw=4 expandtab: */