Summeli

The OpenGL ES frameworks expect to have image size to be powers of two. Therefore we create 256×256 frame and then create our image into it as a sub frame.

Here is an example of opengl es init function.

#include "OpenGLES.h"
_LIT( KTESTDATASNES, "c:\\Data\\test_data\\test_565.mbm");
_LIT( KTESTDATA256x239, "c:\\Data\\test_data\\test_256x239.mbm");
static GLuint    texture;
static GLint format;
static GLint type;
static GLuint textures [2];
static EGLDisplay g_EglDisplay;
static EGLSurface g_EglSurface;

#ifdef OPENGL_ES_BENCHMARK
static CFbsBitmap* iBitmap;
#endif

void InitializeOpenGLES(EGLDisplay aDisplay, EGLSurface aSurface)
{    {
#ifdef OPENGL_ES_BENCHMARK
iBitmap = new (ELeave) CFbsBitmap();
TInt error = iBitmap->Load( KTESTDATA256x239, 0 );
TDisplayMode mode = iBitmap->DisplayMode();
if( mode == EColor64K )
{
// 64k maps to RGB565, which we will use as opengl es texture,
RDebug::Print(_L("Colour mode is correct"));
}

RDebug::Print(_L("ConstructL complete"));
#endif
g_EglDisplay = aDisplay;
g_EglSurface = aSurface;
glClear(GL_COLOR_BUFFER_BIT);
glClearColor(0.0, 0.0, 0.0, 0.0); // set background to black
// Textures are initialized in OpenGL ES API by this function.
glGenTextures( 1, textures[0] );
//Bind the background texture to iTexturesID[0], set the texture environment.
glBindTexture( GL_TEXTURE_2D, textures[0] );

glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB,
256, 256, 0,
GL_RGB, GL_UNSIGNED_SHORT_5_6_5, NULL);

glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glMatrixMode(GL_PROJECTION);
// Push on a new matrix so that we can just pop it off to go back to perspective mode
glDisable( GL_DEPTH_TEST );
glDisable( GL_CULL_FACE  );
// Reset the current matrix to our identify matrix
glLoadIdentity();
// Pass in our 2D ortho screen coordinates (left, right, bottom, top, near, far).
glOrthof( 0, 1, 0, 1, -1, 1 );
// Switch to model view so that we can render the texture
glMatrixMode(GL_MODELVIEW);
// Initialize the current model view matrix with the identity matrix
glLoadIdentity();
glMatrixMode( GL_PROJECTION );
//glEnable( GL_DEPTH_TEST );
//glEnable( GL_CULL_FACE  );
}
}

And then the DeInit function. Only texture is deleted in here. The Screen surface is handled elsewhere.

void DeInitOpenGLES()
{
glDeleteTextures(1, textures[0]);
}

And here is the putframe function. Currently there are

static const GLbyte bgverts[8] =
{
0, 0,
1, 0,
0, 1,
1, 1
};

static const GLubyte bgtex[8] =
{
0, 1,
1, 1,
0, 0,
1, 0
};
//Use rotated matrix for N95, since the phone should be turned upside down.
static const GLubyte rot180_bgtex[8] =
{
1, 0,
0, 0,
1, 1,
0, 1
};
static const GLbyte vertices[3 * 3] =
{
-1,    1,    0,
1,   -1,    0,
1,    1,    0
};

static const GLubyte colors[3 * 4] =
{
255,      0,    0,    255,
0,    255,    0,    255,
0,      0,  255,    255
};

void PutS9xFrame( int aWith, int aHeight )
{
#ifdef OPENGL_ES_BENCHMARK
iBitmap->LockHeap();
TUint8 *data = (TUint8 *) iBitmap->DataAddress();
glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 8, 256, 239,
GL_RGB, GL_UNSIGNED_SHORT_5_6_5, data);

iBitmap->UnlockHeap();
#else
//y-offset8, TODO: calculate this for each resolution
glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 8, 256, 239,
GL_RGB, GL_UNSIGNED_SHORT_5_6_5, GFX.Screen);
#endif

// Enable vertex arrays.
glEnableClientState( GL_VERTEX_ARRAY );
// Set array pointers.
glVertexPointer( 2, GL_BYTE, 0, bgverts );
// Enable texture arrays
glEnableClientState( GL_TEXTURE_COORD_ARRAY );
// Set texture coords
glTexCoordPointer( 2, GL_BYTE, 0, rot180_bgtex );
glEnable(GL_TEXTURE_2D);
glBindTexture( GL_TEXTURE_2D, textures[0] );
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
glDisable(GL_TEXTURE_2D);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glDisableClientState(GL_VERTEX_ARRAY);

// Go back to model view matrix
glMatrixMode( GL_MODELVIEW );
eglSwapBuffers( g_EglDisplay, g_EglSurface);

}

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