The GLSL spec 1.50 (http://www.opengl.org/registry/doc/GLSLangSpec.1.50.09.pdf) at PDF page 99 / labelled page 93, defined the function
ivec2 textureSize (gsampler2DRect sampler)
According ot the preceeding section, the g is used to mean a prefix of “”, “i” or “u”. In my case the prefix is “” as it’s a float sampler.
However, when I try to use this function in my shader:
uniform sampler2DRect Ytex;
void main(){
ivec2 wh = textureSize(Ytex);
}
the shader fails to compile with error C1115: unable to find compatible overloaded function “textureSize(sampler2DRect)”.
What am I doing wrong?