Three.js/GLSL - Convert Pixel Coordinate to World Coordinate

Question

I have a simple shader in my Three.js application that colors the screen red. However, I want to color all pixels to the right of a given world position to to a different co

Answer 1

Answer derived from WestLangley's Fiddle here: http://jsfiddle.net/ST4aM/2/.

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Vertex Shader

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Fragment Shader

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