/*

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_opengles.h"

/* Empty function stub to get OpenGL ES 1.x support without */

/* OpenGL ES extension GL_OES_draw_texture supported */

GL_API void GL_APIENTRY

glDrawTexiOES(GLint x, GLint y, GLint z, GLint width, GLint height)

{

return;

}

/* OpenGL ES 1.1 renderer implementation, based on the OpenGL renderer */

static const float inv255f = 1.0f / 255.0f;

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

static void GLES_WindowEvent(SDL_Renderer * renderer,

const SDL_WindowEvent *event);

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

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

const SDL_Rect * rect, const void *pixels,

int pitch);

static void GLES_UnlockTexture(SDL_Renderer * renderer,

SDL_Texture * texture);

static int GLES_RenderDrawPoints(SDL_Renderer * renderer,

const SDL_Point * points, int count);

static int GLES_RenderDrawLines(SDL_Renderer * renderer,

const SDL_Point * points, int count);

static int GLES_RenderFillRects(SDL_Renderer * renderer,

const SDL_Rect * srcrect,

const SDL_Rect * dstrect);

static void GLES_DestroyTexture(SDL_Renderer * renderer,

SDL_Texture * texture);

static void GLES_DestroyRenderer(SDL_Renderer * renderer);

GLES_CreateRenderer,

{

"opengles",

(SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC),

1,

{SDL_PIXELFORMAT_ABGR8888},

0}

};

typedef struct

{

SDL_GLContext context;

struct {

Uint32 color;

int blendMode;

GLenum scaleMode;

SDL_bool tex_coords;

} current;

SDL_bool useDrawTexture;

SDL_bool GL_OES_draw_texture_supported;

} GLES_RenderData;

typedef struct

{

GLuint texture;

GLenum type;

GLfloat texw;

GLfloat texh;

GLenum format;

GLenum formattype;

void *pixels;

int pitch;

} GLES_TextureData;

static void

GLES_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;

default:

error = "UNKNOWN";

break;

}

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

}

static SDL_GLContext SDL_CurrentContext = NULL;

static int

GLES_ActivateRenderer(SDL_Renderer * renderer)

{

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

if (SDL_CurrentContext != data->context) {

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

return -1;

}

SDL_CurrentContext = data->context;

GLES_UpdateViewport(renderer);

}

return 0;

}

/* This is called if we need to invalidate all of the SDL OpenGL state */

static void

GLES_ResetState(SDL_Renderer *renderer)

{

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

if (SDL_CurrentContext == data->context) {

GLES_UpdateViewport(renderer);

} else {

GLES_ActivateRenderer(renderer);

}

data->current.color = 0;

data->current.blendMode = -1;

data->current.scaleMode = 0;

data->current.tex_coords = SDL_FALSE;

glDisable(GL_DEPTH_TEST);

glDisable(GL_CULL_FACE);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity();

glEnableClientState(GL_VERTEX_ARRAY);

glDisableClientState(GL_TEXTURE_COORD_ARRAY);

}

SDL_Renderer *

GLES_CreateRenderer(SDL_Window * window, Uint32 flags)

{

SDL_Renderer *renderer;

GLES_RenderData *data;

GLint value;

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

if (!renderer) {

SDL_OutOfMemory();

return NULL;

}

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

if (!data) {

GLES_DestroyRenderer(renderer);

SDL_OutOfMemory();

return NULL;

}

renderer->CreateTexture = GLES_CreateTexture;

renderer->UpdateTexture = GLES_UpdateTexture;

renderer->LockTexture = GLES_LockTexture;

renderer->UnlockTexture = GLES_UnlockTexture;

renderer->RenderDrawPoints = GLES_RenderDrawPoints;

renderer->RenderDrawLines = GLES_RenderDrawLines;

renderer->RenderFillRects = GLES_RenderFillRects;

renderer->RenderCopy = GLES_RenderCopy;

renderer->RenderPresent = GLES_RenderPresent;

renderer->DestroyTexture = GLES_DestroyTexture;

renderer->DestroyRenderer = GLES_DestroyRenderer;

SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 1);

SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);

if (!data->context) {

GLES_DestroyRenderer(renderer);

return NULL;

}

GLES_DestroyRenderer(renderer);

return NULL;

}

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;

}

#if SDL_VIDEO_DRIVER_PANDORA

data->GL_OES_draw_texture_supported = SDL_FALSE;

data->useDrawTexture = SDL_FALSE;

#else

if (SDL_GL_ExtensionSupported("GL_OES_draw_texture")) {

data->GL_OES_draw_texture_supported = SDL_TRUE;

data->useDrawTexture = SDL_TRUE;

} else {

data->GL_OES_draw_texture_supported = SDL_FALSE;

data->useDrawTexture = SDL_FALSE;

}

renderer->info.max_texture_height = value;

/* Set up parameters for rendering */

return renderer;

}

static void

GLES_WindowEvent(SDL_Renderer * renderer, const SDL_WindowEvent *event)

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

SDL_CurrentContext = NULL;

}

}

static __inline__ int

power_of_2(int input)

{

int value = 1;

while (value < input) {

value <<= 1;

}

return value;

}

static int

{

GLES_TextureData *data;

GLint internalFormat;

GLenum format, type;

int texture_w, texture_h;

GLenum result;

GLES_ActivateRenderer(renderer);

switch (texture->format) {

case SDL_PIXELFORMAT_ABGR8888:

internalFormat = GL_RGBA;

format = GL_RGBA;

type = GL_UNSIGNED_BYTE;

break;

return -1;

}

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

if (!data) {

SDL_OutOfMemory();

return -1;

}

if (texture->access == SDL_TEXTUREACCESS_STREAMING) {

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

if (!data->pixels) {

SDL_OutOfMemory();

SDL_free(data);

return -1;

}

}

texture->driverdata = data;

glGetError();

glEnable(GL_TEXTURE_2D);

glGenTextures(1, &data->texture);

data->type = GL_TEXTURE_2D;

/* no NPOV textures allowed in OpenGL ES (yet) */

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;

glTexParameteri(data->type, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

glTexParameteri(data->type, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

if (result != GL_NO_ERROR) {

GLES_SetError("glTexImage2D()", result);

return -1;

}

return 0;

}

static int

GLES_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,

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

{

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

Uint8 *blob = NULL;

Uint8 *src;

int srcPitch;

int y;

GLES_ActivateRenderer(renderer);

/* Bail out if we're supposed to update an empty rectangle */

if (rect->w <= 0 || rect->h <= 0)

return 0;

/* Reformat the texture data into a tightly packed array */

srcPitch = rect->w * SDL_BYTESPERPIXEL(texture->format);

src = (Uint8 *)pixels;

if (pitch != srcPitch)

{

blob = (Uint8 *)SDL_malloc(srcPitch * rect->h);

if (!blob)

{

SDL_OutOfMemory();

return -1;

}

src = blob;

for (y = 0; y < rect->h; ++y)

{

SDL_memcpy(src, pixels, srcPitch);

src += srcPitch;

pixels = (Uint8 *)pixels + pitch;

}

src = blob;

}

/* Create a texture subimage with the supplied data */

glGetError();

glEnable(data->type);

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

glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

glTexSubImage2D(data->type,

0,

rect->x,

rect->y,

rect->w,

rect->h,

data->format,

data->formattype,

src);

if (blob) {

SDL_free(blob);

}

if (glGetError() != GL_NO_ERROR)

{

SDL_SetError("Failed to update texture");

return -1;

}

return 0;

}

static int

GLES_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,

{

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

*pixels =

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

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

*pitch = data->pitch;

return 0;

}

static void

GLES_UnlockTexture(SDL_Renderer * renderer, SDL_Texture * texture)

{

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

SDL_Rect rect;

/* We do whole texture updates, at least for now */

rect.x = 0;

rect.y = 0;

rect.w = texture->w;

rect.h = texture->h;

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

}

static int

GLES_UpdateViewport(SDL_Renderer * renderer)

if (SDL_CurrentContext != data->context) {

/* We'll update the viewport after we rebind the context */

return 0;

glViewport(renderer->viewport.x, renderer->viewport.y,

renderer->viewport.w, renderer->viewport.h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

glOrthof((GLfloat) 0,

(GLfloat) renderer->viewport.w,

(GLfloat) renderer->viewport.h,

(GLfloat) 0, 0.0, 1.0);

return 0;

}

static void

GLES_SetColor(GLES_RenderData * data, Uint8 r, Uint8 g, Uint8 b, Uint8 a)

Uint32 color = ((a << 24) | (r << 16) | (g << 8) | b);

if (color != data->current.color) {

glColor4f((GLfloat) r * inv255f,

(GLfloat) g * inv255f,

(GLfloat) b * inv255f,

(GLfloat) a * inv255f);

data->current.color = color;

}

}

switch (blendMode) {

case SDL_BLENDMODE_NONE:

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

glDisable(GL_BLEND);

break;

case SDL_BLENDMODE_BLEND:

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

glEnable(GL_BLEND);

glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

break;

case SDL_BLENDMODE_ADD:

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

glEnable(GL_BLEND);

glBlendFunc(GL_SRC_ALPHA, GL_ONE);

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

glEnable(GL_BLEND);

glBlendFunc(GL_ZERO, GL_SRC_COLOR);

data->current.blendMode = blendMode;

}

}

static void

GLES_SetTexCoords(GLES_RenderData * data, SDL_bool enabled)

{

if (enabled != data->current.tex_coords) {

if (enabled) {

glEnableClientState(GL_TEXTURE_COORD_ARRAY);

} else {

glDisableClientState(GL_TEXTURE_COORD_ARRAY);

}

data->current.tex_coords = enabled;

}

}

static void

GLES_SetDrawingState(SDL_Renderer * renderer)

{

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

GLES_ActivateRenderer(renderer);

GLES_SetColor(data, (GLfloat) renderer->r,

(GLfloat) renderer->g,

(GLfloat) renderer->b,

(GLfloat) renderer->a);

GLES_SetBlendMode(data, renderer->blendMode);

GLES_SetTexCoords(data, SDL_FALSE);

}

static int

GLES_RenderClear(SDL_Renderer * renderer)

{

GLES_ActivateRenderer(renderer);

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

(GLfloat) renderer->g * inv255f,

(GLfloat) renderer->b * inv255f,

(GLfloat) renderer->a * inv255f);

glClear(GL_COLOR_BUFFER_BIT);

return 0;

}

GLES_RenderDrawPoints(SDL_Renderer * renderer, const SDL_Point * points,

int count)

int i;

GLshort *vertices;

vertices = SDL_stack_alloc(GLshort, count*2);

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

vertices[2*i+0] = (GLshort)points[i].x;

vertices[2*i+1] = (GLshort)points[i].y;

}

glVertexPointer(2, GL_SHORT, 0, vertices);

glDrawArrays(GL_POINTS, 0, count);

return 0;

}

GLES_RenderDrawLines(SDL_Renderer * renderer, const SDL_Point * points,

int count)

int i;

GLshort *vertices;

vertices = SDL_stack_alloc(GLshort, count*2);

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

vertices[2*i+0] = (GLshort)points[i].x;

vertices[2*i+1] = (GLshort)points[i].y;

}

if (count > 2 &&

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

/* GL_LINE_LOOP takes care of the final segment */

--count;

return 0;

}

{

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

GLshort minx = rect->x;

GLshort maxx = rect->x + rect->w;

GLshort miny = rect->y;

GLshort maxy = rect->y + rect->h;

GLshort vertices[8];

vertices[0] = minx;

vertices[1] = miny;

vertices[2] = maxx;

vertices[3] = miny;

vertices[4] = minx;

vertices[5] = maxy;

vertices[6] = maxx;

vertices[7] = maxy;

glVertexPointer(2, GL_SHORT, 0, vertices);

glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);

}

static int

GLES_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,

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

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

int minx, miny, maxx, maxy;

GLfloat minu, maxu, minv, maxv;

GLES_ActivateRenderer(renderer);

if (texturedata->scaleMode != data->current.scaleMode) {

glTexParameteri(texturedata->type, GL_TEXTURE_MIN_FILTER,

texturedata->scaleMode);

glTexParameteri(texturedata->type, GL_TEXTURE_MAG_FILTER,

texturedata->scaleMode);

data->current.scaleMode = texturedata->scaleMode;

}

}

GLES_SetTexCoords(data, SDL_TRUE);

if (data->GL_OES_draw_texture_supported && data->useDrawTexture) {

/* this code is a little funny because the viewport is upside down vs SDL's coordinate system */

GLint cropRect[4];

int w, h;

SDL_Window *window = renderer->window;

SDL_GetWindowSize(window, &w, &h);