Texture rendering appears Dull (openGL ES 2.0 iOS) -

ive started opengles2.0 on ios , im trying render texture onto screen.

the problem texture appears different (dull , monochromatic) compared real image supposed render. in sense true colors of texture image isnt reflected while rendering using opengl

the shader program quite simple:

fragment shader

varying lowp vec4 destinationcolor; varying lowp vec2 texcoordout;  uniform sampler2d texture;   void main(void) {     gl_fragcolor = texture2d(texture, texcoordout);  } 

vertex shader

attribute vec4 position;    uniform mat4 projection; uniform mat4 modelview;  attribute vec2 texcoordin; varying vec2 texcoordout;   void main(void) {       gl_position = projection * modelview * position;     texcoordout = texcoordin; } 

the same texturing worked fine on opengl es 1.0, colors showing correctly!

edit:

opengl context setup code:

- (void)setupcontext {        eaglrenderingapi api = keaglrenderingapiopengles2;     _context = [[eaglcontext alloc] initwithapi:api];      if (!_context) {         dlog(@"failed initialize opengles 2.0 context");         exit(1);     }      if (![eaglcontext setcurrentcontext:_context]) {         dlog(@"failed set current opengl context");         exit(1);      } } 

texture loading code:

- (gluint)setuptexture:(uiimage *)image {     glgentextures(1, &texture1);     glbindtexture(gl_texture_2d, texture1);     gltexparameteri(gl_texture_2d,gl_texture_min_filter,gl_linear);     gltexparameteri(gl_texture_2d,gl_texture_mag_filter,gl_linear);      gluint width = cgimagegetwidth(image.cgimage);     gluint height = cgimagegetheight(image.cgimage);     cgcolorspaceref colorspace = cgcolorspacecreatedevicergb();     void *imagedata = malloc( height * width * 4 );     cgcontextref imgcontext = cgbitmapcontextcreate( imagedata, width, height, 8, 4 *   width, colorspace, kcgimagealphapremultipliedlast | kcgbitmapbyteorder32big );     cgcontexttranslatectm (imgcontext, 0, height);     cgcontextscalectm (imgcontext, 1.0, -1.0);     cgcontextsetblendmode(imgcontext, kcgblendmodecopy);     cgcolorspacerelease( colorspace );     cgcontextclearrect( imgcontext, cgrectmake( 0, 0, width, height ) );     cgcontexttranslatectm( imgcontext, 0, height - height );     cgcontextdrawimage( imgcontext, cgrectmake( 0, 0, width, height ), image.cgimage );      glteximage2d(gl_texture_2d, 0, gl_rgba, width, height, 0, gl_rgba, gl_unsigned_byte, imagedata);      cgcontextrelease(imgcontext);      free(imagedata);  return texture1; 

}

second edit: layer setup

 - (void)setuplayer {     _eagllayer = (caeagllayer*) self.layer;     _eagllayer.opaque = yes;     _eagllayer.drawableproperties = [nsdictionary dictionarywithobjectsandkeys:                                 [nsnumber numberwithbool:no],  keagldrawablepropertyretainedbacking, keaglcolorformatrgba8, keagldrawablepropertycolorformat, nil];   } 

ive added piece code layer setup. still no luck!

to preserve colors should initialize opengl 24 or 32 bit color (request config 888 rgb instead of 565 configs). should use 8-bit per channel textures.

does resulting image has green tint? noticeable color distortion in 16-bit color.