Render filter with an offset, scale and rotation.

[JakeCake]

I have a shader that I am trying to use at a specific sprite in my game, but filters seem not to be relative to the sprite, but rather world-pos 0, 0. I would like to render this filter at a different point, but also the "camera"/world may be zoomed in/out and rotated a bit.

 

I am probably looking for a world-matrix of some sort, but can't find one, so I assume it doesn't have one. Here is my shader code for the filter:

this.fragmentSrc = [                // Based on http://glslsandbox.com/e#25456.0        "#ifdef GL_ES",        "precision mediump float;",        "#endif",        // Yuldashev Mahmud Effect took from shaderToy [email protected]        "uniform float time;",        "uniform vec2 mouse;",        "uniform vec2 resolution;",        "uniform vec2 pos;",        "uniform vec2 scale;",        "uniform float rotation;",                "uniform vec4 atmosphereColor;",        "uniform float cloudsStart;",        "uniform float atmosphereEnd;",        "float snoise(vec3 uv, float res)",        "{",            "const vec3 s = vec3(1e0, 1e2, 1e3);",            "uv *= res;",            "vec3 uv0 = floor(mod(uv, res))*s;",            "vec3 uv1 = floor(mod(uv+vec3(1.), res))*s;",            "vec3 f = fract(uv); f = f*f*(3.0-2.0*f);",            "vec4 v = vec4(uv0.x+uv0.y+uv0.z, uv1.x+uv0.y+uv0.z,",                          "uv0.x+uv1.y+uv0.z, uv1.x+uv1.y+uv0.z);",            "vec4 r = fract(sin(v*1e-1)*1e3);",            "float r0 = mix(mix(r.x, r.y, f.x), mix(r.z, r.w, f.x), f.y);",            "r = fract(sin((v + uv1.z - uv0.z)*1e-1)*1e3);",            "float r1 = mix(mix(r.x, r.y, f.x), mix(r.z, r.w, f.x), f.y);",            "return mix(r0, r1, f.z)*2.-1.;",        "}",        "void main( void ) {",                    "vec2 UV = pos.xy / resolution.xy + gl_FragCoord.xy / resolution.xy * scale.xy;",                    "UV.x *= resolution.x / resolution.y;",            "UV /= cloudsStart;",                        // ATMOSPHERE            "float finalAtmosphere = 1.0 - (length(UV) / atmosphereEnd);",                    "finalAtmosphere = max(.0, finalAtmosphere);",                        "gl_FragColor = vec4(finalAtmosphere);",                "}",            ];

Do we have an expert on this subject? If I could just access the world-matrix I think everything would work out. Otherwise, maybe I can do something we a rendertexture or alike and then translate it afterwards. I'm looking for a performance effective way that solves this problem.

 

What I have now is something that seems to work as long as the player is in 0, 0 compared to the sprite with the filter, but when moving away it starts to rotate funny and offset as well.