test1.frag.glsl 1.4 KB

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  1. #version 120
  2. // Taken from mts3d forums, from user fredrik.
  3. uniform sampler2D warpTexture;
  4. const vec2 LeftLensCenter = vec2(0.2863248, 0.5);
  5. const vec2 RightLensCenter = vec2(0.7136753, 0.5);
  6. const vec2 LeftScreenCenter = vec2(0.25, 0.5);
  7. const vec2 RightScreenCenter = vec2(0.75, 0.5);
  8. const vec2 Scale = vec2(0.1469278, 0.2350845);
  9. const vec2 ScaleIn = vec2(4, 2.5);
  10. const vec4 HmdWarpParam = vec4(1, 0.22, 0.24, 0);
  11. // Scales input texture coordinates for distortion.
  12. vec2 HmdWarp(vec2 in01, vec2 LensCenter)
  13. {
  14. vec2 theta = (in01 - LensCenter) * ScaleIn; // Scales to [-1, 1]
  15. float rSq = theta.x * theta.x + theta.y * theta.y;
  16. vec2 rvector = theta * (HmdWarpParam.x + HmdWarpParam.y * rSq +
  17. HmdWarpParam.z * rSq * rSq +
  18. HmdWarpParam.w * rSq * rSq * rSq);
  19. return LensCenter + Scale * rvector;
  20. }
  21. void main()
  22. {
  23. // The following two variables need to be set per eye
  24. vec2 LensCenter = gl_FragCoord.x < 640 ? LeftLensCenter : RightLensCenter;
  25. vec2 ScreenCenter = gl_FragCoord.x < 640 ? LeftScreenCenter : RightScreenCenter;
  26. vec2 oTexCoord = gl_FragCoord.xy / vec2(1280, 800);
  27. vec2 tc = HmdWarp(oTexCoord, LensCenter);
  28. if (any(bvec2(clamp(tc,ScreenCenter-vec2(0.25,0.5), ScreenCenter+vec2(0.25,0.5)) - tc)))
  29. {
  30. gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0);
  31. return;
  32. }
  33. tc.x = gl_FragCoord.x < 640 ? (2.0 * tc.x) : (2.0 * (tc.x - 0.5));
  34. gl_FragColor = texture2D(warpTexture, tc);
  35. }