Moved selection of I915 hack out of the YUV shader.

client/deps/glbench/src/yuv2rgb_1.glslf

 /*
  * Copyright 2010, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 15 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 /*
  * This is a conversion of a cg shader from Chrome:
  * http://src.chromium.org/viewvc/chrome/trunk/src/o3d/samples/shaders/yuv2rgb.shader
  */
-#define I915_WORKAROUND 1
 
 /*
  * This shader takes a Y'UV420p image as a single greyscale plane, and
  * converts it to RGB by sampling the correct parts of the image, and
  * by converting the colorspace to RGB on the fly.
  */
 
 /*
  * These represent the image dimensions of the SOURCE IMAGE (not the
  * Y'UV420p image).  This is the same as the dimensions of the Y'
@@ skipping 124 matching lines @@
  * 0  +---+---+---+---+
  *    0               1
  *
  */
 void main() {
   /*
    * Calculate what image pixel we're on, since we have to calculate
    * the location in the image stream, using floor in several places
    * which makes it hard to use parametric coordinates.
    */
-#if I915_WORKAROUND
+#if defined(I915_WORKAROUND)
   vec2 pixelPosition = vec2(floor(imageWidth * gl_TexCoord[0].x),
                             floor(imageHeight * gl_TexCoord[0].y));
 #else
   vec2 pixelPosition = vec2(floor(imageWidth * v1.x),
                             floor(imageHeight * v1.y));
 #endif
 
   /*
    * We can use the parametric coordinates to get the Y channel, since it's
    * a relatively normal image.
    */
-#if I915_WORKAROUND
+#if defined(I915_WORKAROUND)
   float yChannel = getYPixel(vec2(gl_TexCoord[0]));
 #else
   float yChannel = getYPixel(vec2(v1));
 #endif
 
   /*
    * As noted above, the U and V planes are smashed onto the end of
    * the image in an odd way (in our 2D texture mapping, at least), so
    * these mapping functions take care of that oddness.
    */
   float uChannel = texture2D(textureSampler, mapU(pixelPosition)).x;
   float vChannel = texture2D(textureSampler, mapV(pixelPosition)).x;
 
   /*
    * This does the colorspace conversion from Y'UV to RGB as a matrix
    * multiply.  It also does the offset of the U and V channels from
    * [0,1] to [-.5,.5] as part of the transform.
    */
   vec4 channels = vec4(yChannel, uChannel, vChannel, 1.0);
   mat4 conversion = mat4( 1.0,    1.0,    1.0,   0.0,
                           0.0,   -0.344,  1.772, 0.0,
                           1.402, -0.714,  0.0,   0.0,
                          -0.701,  0.529, -0.886, 1.0);
 
   gl_FragColor = conversion * channels;
 }