Linking one uniform variable to many shaders
- by Winged
Let's say, that I have 3 programs, and in each of those programs there is a view matrix uniform, which should be the same in all those programs.
Right now, when my camera moves, I need to re-upload the modified matrix to every program separately. Is it possible to create some kind of global uniforms which are constant for all programs linked to it, so I could just upload the matrix once?
I tried creating a globalUniforms object which looked kinda like this:
var globalUniforms = {
program: {},
// (...)
vMatrixUniform: null,
// (...)
initialize: function() {
vMatrixUniform = gl.getUniformLocation(this.program, 'uVMatrix');
}
};
So I could just link it to proper programs like this: program.vMatrixUniform = globalUniforms.vMatrixUniform;, and then pass the matrix like this:
if (camera.isDirty.viewMatrix !== false) { camera.isDirty.viewMatrix = false;
gl.uniformMatrix4fv(globalUniforms.vMatrixUniform, false, camera.viewMatrix.element);
}
but unfortunately it throws an error:
Uncaught exception: gl.INVALID_VALUE was caused by call to:
getUniformLocation called from line 272, column 2 in () in mysite/js/mesh.js:
vMatrixUniform = gl.getUniformLocation(this.program, 'uVMatrix');
Summing up: is there a more efficient way of managing shaders which follows my logic?
