/*

SDL - Simple DirectMedia Layer

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"

#include "SDL_opengl.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/documentation/GraphicsImaging/Conceptual/OpenGL-MacProgGuide/opengl_texturedata/chapter_10_section_2.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 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,

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 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",

1,

{SDL_PIXELFORMAT_ARGB8888},

0,

0}

};

typedef struct

{

SDL_GLContext context;

int blendMode;

/* OpenGL functions */

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

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

const GLvoid * pointer);

} GL_RenderData;

typedef struct

{

GLuint texture;

GLfloat texw;

GLfloat texh;

GLenum format;

GLenum formattype;

void *pixels;

int pitch;

} 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__ */

#undef SDL_PROC

return 0;

}

SDL_Renderer *

GL_CreateRenderer(SDL_Window * window, Uint32 flags)

{

SDL_Renderer *renderer;

GL_RenderData *data;

window_flags = SDL_GetWindowFlags(window);

if (!(window_flags & SDL_WINDOW_OPENGL)) {

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

return NULL;

}

}

if (!renderer) {

SDL_OutOfMemory();

return NULL;

}

if (!data) {

GL_DestroyRenderer(renderer);

SDL_OutOfMemory();

return NULL;

}

renderer->CreateTexture = GL_CreateTexture;

renderer->UpdateTexture = GL_UpdateTexture;

renderer->LockTexture = GL_LockTexture;

renderer->UnlockTexture = GL_UnlockTexture;

renderer->RenderClear = GL_RenderClear;

renderer->RenderDrawPoints = GL_RenderDrawPoints;

renderer->RenderDrawLines = GL_RenderDrawLines;

renderer->RenderFillRects = GL_RenderFillRects;

renderer->RenderPresent = GL_RenderPresent;

renderer->DestroyTexture = GL_DestroyTexture;

renderer->DestroyRenderer = GL_DestroyRenderer;

renderer->info = GL_RenderDriver.info;

renderer->driverdata = data;

if (GL_LoadFunctions(data) < 0) {

GL_DestroyRenderer(renderer);

return NULL;

}

if (!data->context) {

GL_DestroyRenderer(renderer);

return NULL;

}

GL_DestroyRenderer(renderer);

return NULL;

}

#ifdef __MACOSX__

/* Enable multi-threaded rendering */

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

CGLEnable(CGLGetCurrentContext(), kCGLCEMPEngine);

*/

#endif

SDL_GL_SetSwapInterval(1);

} else {

SDL_GL_SetSwapInterval(0);

}

if (SDL_GL_GetSwapInterval() > 0) {

}

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");

}

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);*/

return renderer;

}

static SDL_GLContext SDL_CurrentContext = NULL;

static int

GL_ActivateRenderer(SDL_Renderer * renderer)

{

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

if (SDL_CurrentContext != data->context) {

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

return -1;

}

SDL_CurrentContext = data->context;

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)

case SDL_PIXELFORMAT_RGB888:

case SDL_PIXELFORMAT_ARGB8888:

*internalFormat = GL_RGBA8;

*format = GL_BGRA;

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;

}

if (!data) {

SDL_OutOfMemory();

return -1;

}

data->pixels = SDL_malloc(texture->h * data->pitch);

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

}

data->format = format;

data->formattype = type;

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

GL_CLAMP_TO_EDGE);

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

GL_CLAMP_TO_EDGE);

#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);

}

if (result != GL_NO_ERROR) {

GL_SetError("glTexImage2D()", result);

return -1;

}

return 0;

}

SetupTextureUpdate(GL_RenderData * renderdata, SDL_Texture * texture,

int pitch)

}

static int

GL_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,

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

{

GL_ActivateRenderer(renderer);

renderdata->glGetError();

SetupTextureUpdate(renderdata, texture, pitch);

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 (result != GL_NO_ERROR) {

GL_SetError("glTexSubImage2D()", result);

return -1;

}

return 0;

}

static int

GL_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,

{

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

*pixels =

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

return 0;

}

static void

GL_UnlockTexture(SDL_Renderer * renderer, SDL_Texture * texture)

{

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

GL_ActivateRenderer(renderer);

SetupTextureUpdate(renderdata, texture, data->pitch);

renderdata->glEnable(data->type);

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

renderdata->glTexSubImage2D(data->type, 0, 0, 0, texture->w, texture->h,

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

renderdata->glDisable(data->type);

}

{

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;

}

}

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;

GL_ActivateRenderer(renderer);

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);

}

return 0;

}

GL_RenderDrawLines(SDL_Renderer * renderer, const SDL_Point * points,

int count)

{

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

GL_ActivateRenderer(renderer);

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 {

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);

/* 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);

x1 = points[0].x;

y1 = points[0].y;

x2 = points[count-1].x;

y2 = points[count-1].y;