I need an Edge Dilation Filter GLSL!!


I have a trouble. I have an image, and a shadowmap of this image done. Trough the shadowmap and applying a sobel edge filter i could find the contours of the shadowmap. Now my purpose is to dilate them. Unfortunately i could not find any example of this here except this one made by PocketMoon:


Unfortunately i don’t have acess to this file, and i can’t seem to find any similar example in the internet! Can anyone help me? Here’s my project. What do i have to code/do? http://rapidshare.com/files/265864726/Shadow_Mapping_with_GLSL.zip.html

I have seen dilation fragment shader in OpenGL Super Bible, I don’t remember it, but the idea was simple. Take 9 samples (3x3) (if You already have convolution filters it should be easy), and write maximum of them (brightest) as output.

Yes, but my main problem is not about knowing how the shader works, but how to transport the framebuffer into a texture that the shader will receive and modify…in this case my program should have 2 shaders, first the sobel filter one, and second the dilation one. I just don’t know how to make the interaction between them, wich means i dont know how the dilation filter can receive the result of the sobel filter to make the dilation. How can i code/pseudo code that in GLSL?