Hi. I'm new to GLSL, so I suspect I've done something silly here. I have a very basic shader. vec4 effect(vec4 color, sampler2D texture, vec2 texture_coords, vec2 screen_coords) { int blur_size = 16; float x_pixel_size = 1.0 / 800.0; float y_pixel_size = 1.0 / 600.0; vec4 sum; for (int i = -blur_siz...