//Read texture coordinates
"vec2 texCoord = gl_TexCoord[0].xy;"
//Read value of texture of current pixel
"vec4 original_value = texture2DRect(texture,texCoord);"
Q1:
The gl_TexCoord[0].xy will return the coordinates (x,y) of the texture[0] to the vec2 texCoord right?
Eg: if (x,y) = (1,2);
texCoord = (1,2) right?
Q2: I only have one component on each pixels of the texture. So, texture2DRect(texture,texCoord) will return 4 values to the original_value.
Eg: If the texture value is 2, the original_value = (2,0,0,0)?
The rest of the value will be zero or how?