i'm pretty much into pixel shader lately, and it's going pretty well so far. but one thing that bothers me, is that i don't have any clue about antialiasing/smoothing hard edges, which occur, when i want to tile ranges between 0.0 and 1.0. a common practice when tiling values is using mod or fract.
currently, i try to develope a shader which can tile/offset/rotate a sprite's texture like on the following image. as you can see, fract introduces nasty jaggies, which i like to get rid off.
on my research, i found a pretty interesting tutorial that deals with a halftone shader, which can be found here and sheds light on antialiasing as well. in step "3. Anti-aliasing is required" it is mentioned that we normally use dFdx() and dFdy() or fwidth to determine automatic derivatives which can interpolate our rough fract values painlessly. but since this cool webgl extension is not enabled within C2, we have to find other options to smooth out jaggies by finding customized versions of our functions.
so my question is, perhaps @Ashley , how are the pre-defined uniforms pixelWidth/pixelHeight connected to those unavailable functions dFdx/dFdy/fWidth and how can i achieve a smoothing on hard edges between 0.0 and 1.0 maybe with the help of pixelWidth/Height? i really like to offer some generative shaders to the community with some sort of antialiasing... please help me out on this one.