texture2DLod() can't be found

Hello,

I’m trying to avoid seams when tiling a surface with textures from texture atlas (the problem and possible solution can be found here: Terrain engine | IceFall Games)
I need to manually calculate mipmap level in GLSLES fragment shader and thus use texture2DLod() function.
Here is my fragment shader:


#extension GL_OES_standard_derivatives : enable

precision mediump float;

varying vec2 vUV0;
uniform sampler2D textureA;


float mipmapLevel(in vec2 coords, in vec2 texSize)
{
	vec2 coordInPix = coords * texSize;
	vec2 dx = dFdx(coordInPix);
	vec2 dy = dFdy(coordInPix);
	float d = max(dot(dx, dx), dot(dy, dy));
	return 0.4 * log2(d);
}


void main(void)
{
	vec4 colorOut;
	
	vec2 uv = vUV0;
	
	// wrapping the coordinates
	uv = fract(uv);
	// recalculating them into atlas
	uv = 64.0/512.0 + uv*128.0/512.0;;
	
	
	float lod = mipmapLevel(uv, vec2(512.0, 512.0));
	
	colorOut = texture2DLod(textureA, uv, lod);
	
	gl_FragColor = colorOut;	
}

I’m getting the following error message from shader compiler: " ‘texture2DLod’ : no matching overloaded function found "

According to my googling, texture2DLod can be used in fragment shader (though OGL specs say it should be used only in vertex shader - maybe a misprint).
I’ve tried defining extensions such as GL_EXT_shader_texture_lod, but none of them are accepted by the shader compiler.

Did I go wrong somewhere, or texture2DLod() is just supported by a narrow range of hardware?

My videocard is GeForce N210, also I tried my app on Samsung GalaxyTab with no result.

This topic was automatically closed 183 days after the last reply. New replies are no longer allowed.