Fix crucial data sampling bugs

Author: Rsnelllenberg

DVRViewPlugin/res/shaders/FullDataSampling.comp

@@ -153,11 +153,11 @@ void main()
 
             // Update brick counters in x-first order.
             bx++;
-            if (bx > int(atlasLayout.x))
+            if (bx >= int(atlasLayout.x))
             {
                 bx = 0;
                 by++;
-                if (by > int(atlasLayout.y))
+                if (by >= int(atlasLayout.y))
                 {
                     by = 0;
                     bz++;

DVRViewPlugin/src/VolumeRenderer.cpp

@@ -1069,9 +1069,6 @@ void VolumeRenderer::getGPUFullDataModeBatches(std::vector<float>& frontfacesDat
     {
         for (int idx = batchIndex; idx < width * height; idx += numBatches)
         {
-            // Skip pixel if it does not hit the volume.
-            if (frontfacesData[idx * 3] == 0.0f)
-                continue;
 
             // Get positions from the textures.
             mv::Vector3f frontPos(