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Initial pixel shader support for YUV textures in the GL renderer.
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@icculus
icculus committed Dec 6, 2008
1 parent 61ef0f1 commit dbc88d3
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Showing 2 changed files with 199 additions and 9 deletions.
2 changes: 1 addition & 1 deletion src/video/SDL_glfuncs.h
View file
Expand Up @@ -153,7 +153,7 @@ SDL_PROC_UNUSED(void, glGetPixelMapuiv, (GLenum map, GLuint * values))
SDL_PROC_UNUSED(void, glGetPixelMapusv, (GLenum map, GLushort * values))
SDL_PROC_UNUSED(void, glGetPointerv, (GLenum pname, GLvoid * *params))
SDL_PROC_UNUSED(void, glGetPolygonStipple, (GLubyte * mask))
SDL_PROC_UNUSED(const GLubyte *, glGetString, (GLenum name))
SDL_PROC(const GLubyte *, glGetString, (GLenum name))
SDL_PROC_UNUSED(void, glGetTexEnvfv,
(GLenum target, GLenum pname, GLfloat * params))
SDL_PROC_UNUSED(void, glGetTexEnviv,
Expand Down
206 changes: 198 additions & 8 deletions src/video/SDL_renderer_gl.c
View file
Expand Up @@ -41,6 +41,21 @@
http://developer.apple.com/documentation/GraphicsImaging/Conceptual/OpenGL-MacProgGuide/opengl_texturedata/chapter_10_section_2.html
*/

/* !!! FIXME: this should go in a higher level than the GL renderer. */
static __inline__ int
bytes_per_pixel(const Uint32 format)
{
switch (format) {
case SDL_PIXELFORMAT_UYVY:
/* !!! FIXME: other YUV formats here... */
return 2;
default:
return SDL_BYTESPERPIXEL(format);
}
return -1; /* shouldn't ever hit this. */
}


static const float inv255f = 1.0f / 255.0f;

static SDL_Renderer *GL_CreateRenderer(SDL_Window * window, Uint32 flags);
Expand Down Expand Up @@ -124,6 +139,7 @@ typedef struct
SDL_bool updateSize;
SDL_bool GL_ARB_texture_rectangle_supported;
SDL_bool GL_EXT_paletted_texture_supported;
SDL_bool GL_ARB_fragment_program_supported;
int blendMode;
int scaleMode;

Expand All @@ -135,11 +151,23 @@ typedef struct
PFNGLCOLORTABLEEXTPROC glColorTableEXT;
void (*glTextureRangeAPPLE) (GLenum target, GLsizei length,
const GLvoid * pointer);

PFNGLGETPROGRAMIVARBPROC glGetProgramivARB;
PFNGLGETPROGRAMSTRINGARBPROC glGetProgramStringARB;
PFNGLPROGRAMLOCALPARAMETER4FVARBPROC glProgramLocalParameter4fvARB;
PFNGLDELETEPROGRAMSARBPROC glDeleteProgramsARB;
PFNGLGENPROGRAMSARBPROC glGenProgramsARB;
PFNGLBINDPROGRAMARBPROC glBindProgramARB;
PFNGLPROGRAMSTRINGARBPROC glProgramStringARB;

/* (optional) fragment programs */
GLuint fragment_program_UYVY;
} GL_RenderData;

typedef struct
{
GLuint texture;
GLuint shader;
GLenum type;
GLfloat texw;
GLfloat texh;
Expand Down Expand Up @@ -348,6 +376,28 @@ GL_CreateRenderer(SDL_Window * window, Uint32 flags)
SDL_GL_GetProcAddress("glTextureRangeAPPLE");
}

/* we might use fragment programs for YUV data, etc. */
if (SDL_GL_ExtensionSupported("GL_ARB_fragment_program")) {
/* !!! FIXME: this doesn't check for errors. */
/* !!! FIXME: this should really reuse the glfuncs.h stuff. */
data->glGetProgramivARB = (PFNGLGETPROGRAMIVARBPROC)
SDL_GL_GetProcAddress("glGetProgramivARB");
data->glGetProgramStringARB = (PFNGLGETPROGRAMSTRINGARBPROC)
SDL_GL_GetProcAddress("glGetProgramStringARB");
data->glProgramLocalParameter4fvARB =
(PFNGLPROGRAMLOCALPARAMETER4FVARBPROC)
SDL_GL_GetProcAddress("glProgramLocalParameter4fvARB");
data->glDeleteProgramsARB = (PFNGLDELETEPROGRAMSARBPROC)
SDL_GL_GetProcAddress("glDeleteProgramsARB");
data->glGenProgramsARB = (PFNGLGENPROGRAMSARBPROC)
SDL_GL_GetProcAddress("glGenProgramsARB");
data->glBindProgramARB = (PFNGLBINDPROGRAMARBPROC)
SDL_GL_GetProcAddress("glBindProgramARB");
data->glProgramStringARB = (PFNGLPROGRAMSTRINGARBPROC)
SDL_GL_GetProcAddress("glProgramStringARB");
data->GL_ARB_fragment_program_supported = SDL_TRUE;
}

/* Set up parameters for rendering */
data->blendMode = -1;
data->scaleMode = -1;
Expand Down Expand Up @@ -406,6 +456,103 @@ power_of_2(int input)
return value;
}


#define DEBUG_PROGRAM_COMPILE 1

static GLuint
compile_shader(GL_RenderData *data, GLenum shader_type, const char *source)
{
#if DEBUG_PROGRAM_COMPILE
printf("compiling shader:\n%s\n\n", source);
#endif

GLuint program = 0;

data->glGetError(); /* flush any existing error state. */
data->glGenProgramsARB(1, &program);
data->glBindProgramARB(shader_type, program);
data->glProgramStringARB(shader_type, GL_PROGRAM_FORMAT_ASCII_ARB,
SDL_strlen(source), source);

if (data->glGetError() == GL_INVALID_OPERATION)
{
#if DEBUG_PROGRAM_COMPILE
GLint pos = 0;
const GLubyte *errstr;
data->glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &pos);
errstr = data->glGetString(GL_PROGRAM_ERROR_STRING_ARB);
printf("program compile error at position %d: %s\n\n",
(int) pos, (const char *) errstr);
#endif
data->glBindProgramARB(shader_type, 0);
data->glDeleteProgramsARB(1, &program);
return 0;
} // if

return program;
}

// UYVY to RGB equasion...
// R = 1.164(Y-16) + 1.596(Cr-128)
// G = 1.164(Y-16) - 0.813(Cr-128) - 0.391(Cb-128)
// B = 1.164(Y-16) + 2.018(Cb-128)
// Byte layout is Cb, Y1, Cr, Y2.
// 4 bytes == 2 pixels: Y1/Cb/Cr, Y2/Cb/Cr
// !!! FIXME: this ignores blendmodes, etc.
// !!! FIXME: this could be more efficient...use a dot product for green, not convert to 255.0 range, etc.
static const char *fragment_program_UYVY_source_code =
"!!ARBfp1.0\n"

// outputs...
"OUTPUT outcolor = result.color;\n"

// scratch registers...
"TEMP uyvy;\n"
"TEMP luminance;\n"
"TEMP work;\n"

// We need 32 bits to store the data, but each pixel is 16 bits in itself.
// halve the coordinates to grab the correct 32 bits for the fragment.
"MUL work, fragment.texcoord, { 0.5, 1.0, 1.0, 1.0 };\n"

// Sample the YUV texture. Cb, Y1, Cr, Y2, are stored in r,g,b,a.
// !!! FIXME: "RECT" needs to be "2D" if we're not using texture_rectangle extension. :/
"TEX uyvy, work, texture[0], RECT;\n"

// Scale from 0.0/1.0 to 0.0/255.0 and do subtractions. (!!! FIXME: optimize!)
"MUL uyvy, uyvy, { 255.0, 255.0, 255.0, 255.0 };\n"
"SUB uyvy, uyvy, { 128.0, 16.0, 128.0, 16.0 };\n"

// Choose the luminance component by texcoord.
// !!! FIXME: laziness wins out for now... just average Y1 and Y2.
"ADD luminance, uyvy.yyyy, uyvy.wwww;\n"
"MUL luminance, luminance, { 0.5, 0.5, 0.5, 0.5 };\n"

// Multiply luminance by its magic value.
"MUL luminance, luminance, { 1.164, 1.164, 1.164, 1.164 };\n"

// uyvy.xyzw becomes Cr/Cr/Cb/Cb, with multiplications.
"MUL uyvy, uyvy.zzxx, { 1.596, -0.813, 2.018, -0.391 };\n"

// Add luminance Cr and Cb, store to RGB channels.
"ADD work.rgb, luminance, uyvy;\n"

// Do final addition for Green channel. (!!! FIXME: this should be a DPH?)
"ADD work.g, work.g, uyvy.w;\n"

// Scale back to 0.0/1.0. (this number is 1.0/255.0).
"MUL work, work, { 0.0039215686274509803, 0.0039215686274509803, 0.0039215686274509803, 0.0039215686274509803 };\n"

// Make sure alpha channel is fully opaque. (!!! FIXME: blend modes!)
"MOV work.a, { 1.0 };\n"

// Store out the final fragment color.
"MOV outcolor, work;\n"

// ...and we're done.
"END\n";


static int
GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
{
Expand All @@ -415,6 +562,7 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
GLint internalFormat;
GLenum format, type;
int texture_w, texture_h;
GLuint shader = 0;
GLenum result;

switch (texture->format) {
Expand Down Expand Up @@ -504,6 +652,26 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
format = GL_BGRA;
type = GL_UNSIGNED_INT_2_10_10_10_REV;
break;
case SDL_PIXELFORMAT_UYVY:
if (renderdata->GL_ARB_fragment_program_supported) {
if (renderdata->fragment_program_UYVY == 0) {
renderdata->fragment_program_UYVY =
compile_shader(renderdata, GL_FRAGMENT_PROGRAM_ARB,
fragment_program_UYVY_source_code);
if (renderdata->fragment_program_UYVY == 0) {
SDL_SetError("Fragment program compile error");
return -1;
}
}
shader = renderdata->fragment_program_UYVY;
internalFormat = GL_RGBA;
format = GL_RGBA;
type = GL_UNSIGNED_BYTE;
} else {
SDL_SetError("Unsupported texture format");
return -1;
}
break;
default:
SDL_SetError("Unsupported texture format");
return -1;
Expand All @@ -515,6 +683,8 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
return -1;
}

data->shader = shader;

if (texture->format == SDL_PIXELFORMAT_INDEX8) {
data->palette = (Uint8 *) SDL_malloc(3 * 256 * sizeof(Uint8));
if (!data->palette) {
Expand All @@ -526,7 +696,7 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
}

if (texture->access == SDL_TEXTUREACCESS_STREAMING) {
data->pitch = texture->w * SDL_BYTESPERPIXEL(texture->format);
data->pitch = texture->w * bytes_per_pixel(texture->format);
data->pixels = SDL_malloc(texture->h * data->pitch);
if (!data->pixels) {
SDL_OutOfMemory();
Expand All @@ -543,15 +713,16 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
data->type = GL_TEXTURE_RECTANGLE_ARB;
texture_w = texture->w;
texture_h = texture->h;
data->texw = (GLfloat) texture->w;
data->texh = (GLfloat) 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->texw = (GLfloat) (texture->w) / texture_w;
data->texh = (GLfloat) texture->h / texture_h;
}

data->format = format;
data->formattype = type;
renderdata->glBindTexture(data->type, data->texture);
Expand All @@ -563,7 +734,7 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
GL_CLAMP_TO_EDGE);
renderdata->glTexParameteri(data->type, GL_TEXTURE_WRAP_T,
GL_CLAMP_TO_EDGE);
#ifdef __MACOSX__
#if 0 //def __MACOSX__
#ifndef GL_TEXTURE_STORAGE_HINT_APPLE
#define GL_TEXTURE_STORAGE_HINT_APPLE 0x85BC
#endif
Expand Down Expand Up @@ -598,6 +769,7 @@ GL_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
#endif
#endif
{
printf("teximage2d(%d,%d,%d,%d)\n", (int) texture_w, (int) texture_h);
renderdata->glTexImage2D(data->type, 0, internalFormat, texture_w,
texture_h, 0, format, type, NULL);
}
Expand Down Expand Up @@ -679,7 +851,7 @@ SetupTextureUpdate(GL_RenderData * renderdata, SDL_Texture * texture,
}
renderdata->glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
renderdata->glPixelStorei(GL_UNPACK_ROW_LENGTH,
pitch / SDL_BYTESPERPIXEL(texture->format));
pitch / bytes_per_pixel(texture->format));
}

static int
Expand Down Expand Up @@ -741,6 +913,7 @@ GL_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,
renderdata->glGetError();
SetupTextureUpdate(renderdata, texture, pitch);
renderdata->glBindTexture(data->type, data->texture);
printf("texsubimage2d(%d,%d,%d,%d)\n", (int) rect->x, (int) rect->y, (int) rect->w, (int) rect->h);
renderdata->glTexSubImage2D(data->type, 0, rect->x, rect->y, rect->w,
rect->h, data->format, data->formattype,
pixels);
Expand All @@ -765,7 +938,7 @@ GL_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,

*pixels =
(void *) ((Uint8 *) data->pixels + rect->y * data->pitch +
rect->x * SDL_BYTESPERPIXEL(texture->format));
rect->x * bytes_per_pixel(texture->format));
*pitch = data->pitch;
return 0;
}
Expand Down Expand Up @@ -814,7 +987,7 @@ GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
if (texturedata->dirty.list) {
SDL_DirtyRect *dirty;
void *pixels;
int bpp = SDL_BYTESPERPIXEL(texture->format);
int bpp = bytes_per_pixel(texture->format);
int pitch = texturedata->pitch;

SetupTextureUpdate(data, texture, pitch);
Expand All @@ -824,6 +997,7 @@ GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
pixels =
(void *) ((Uint8 *) texturedata->pixels + rect->y * pitch +
rect->x * bpp);
printf("texsubimage2d(%d,%d,%d,%d)\n", (int) rect->x, (int) rect->y, (int) rect->w, (int) rect->h);
data->glTexSubImage2D(texturedata->type, 0, rect->x, rect->y,
rect->w, rect->h, texturedata->format,
texturedata->formattype, pixels);
Expand Down Expand Up @@ -902,6 +1076,11 @@ GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
data->scaleMode = texture->scaleMode;
}

if (texturedata->shader != 0) {
data->glEnable(GL_FRAGMENT_PROGRAM_ARB);
data->glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, texturedata->shader);
}

data->glBegin(GL_TRIANGLE_STRIP);
data->glTexCoord2f(minu, minv);
data->glVertex2i(minx, miny);
Expand All @@ -913,6 +1092,9 @@ GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
data->glVertex2i(maxx, maxy);
data->glEnd();

if (texturedata->shader != 0) {
data->glDisable(GL_FRAGMENT_PROGRAM_ARB);
}
return 0;
}

Expand Down Expand Up @@ -952,6 +1134,14 @@ GL_DestroyRenderer(SDL_Renderer * renderer)

if (data) {
if (data->context) {
if (data->GL_ARB_fragment_program_supported) {
data->glDisable(GL_FRAGMENT_PROGRAM_ARB);
data->glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, 0);
if (data->fragment_program_UYVY != 0) {
data->glDeleteProgramsARB(1, &data->fragment_program_UYVY);
}
}

/* SDL_GL_MakeCurrent(0, NULL); *//* doesn't do anything */
SDL_GL_DeleteContext(data->context);
}
Expand Down

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