ofxShader Convolution[SOLVED]

What a great duo of addons with ofxFboTexture and ofxShader!

I’ve built a few shaders now by going through the orange book, but my recent attempt at a convolution shader with a 3x3 kernel is not going well.

Trying laplace edge detection first, but it only works if I multiply my kernel by 100 or so. Something must be wrong.

*EDIT - [SOLVED] - If any one else is having problems, here’s how I figured it out.

GL_TEXTURE_2D has texture coordinates from (0, 0) to (1, 1).
GL_TEXTURE_RECTANGLE_ARB has texture coordinates from (0, 0) to (width, height)!!!

This is a very important difference I did not understand.

Good luck.