documentation

Author: dlacewellNV

src/optixGlass/README.md

@@ -4,5 +4,8 @@ optixGlass
 
 ![Glass Teapot](./optixGlass.png)
 
-A physically based glass shader example, using path tracing.
+A physically based glass shader example, using path tracing.  Drag the sliders around to change the color of the glass.
+
+Scene credit: 
+[Benedikt Bitterli](https://benedikt-bitterli.me/resources)
 

src/optixVox/README.md

@@ -5,7 +5,8 @@ optixVox
 ![VOX scene](./optixVox.png)
 
 A sample that renders a subset of the [MagicaVoxel @ ephtracy](https://ephtracy.github.io/) 8-bit VOX file format, using path tracing.
-This is not volume rendering; "voxels" are solid boxes.
+This is not volume rendering; "voxels" are solid boxes.  Give multiple files on the command line to load them all and arrange them in
+a grid.
 
 Scene credit: 
 [Mike Judge](https://github.com/mikelovesrobots/mmmm)

src/optixVox/boxes.cu

@@ -27,6 +27,20 @@
  */
 
 
+// Intersection and bounds programs for custom box prims as the leaf nodes of a
+// BVH.  The boxes are represented as 4 bytes per box (VOX format).
+
+// Note: 
+// This is a compromise between intersection cost and memory cost: a BVH
+// built over triangles could be faster to intersect, but would use more memory
+// for the leaves (12 triangles per box), while an intersector that handled
+// larger chunks of boxes via 3d grid traversal would be slower but would
+// reduce the size of the BVH.  The compromise solution seems fine for a single
+// VOX file (max 256**3 boxes) or a handful of files.  The custom 3d grid
+// intersector could be interesting for very large scenes, e.g., Minecraft
+// files, that might have far more than 256**3 boxes.
+
+
 #include <optix.h>
 #include <optixu/optixu_math_namespace.h>
 #include <optixu/optixu_matrix_namespace.h>
@@ -36,7 +50,7 @@
 
 using namespace optix;
 
-// Compressed 8-bit indices as in VOX format.  We expand these into floating point coords during intersection.
+// 8-bit indices as in VOX format.  We expand these into floating point coords during intersection.
 rtBuffer< optix::uchar4 > box_buffer;
 
 rtBuffer< optix::uchar4 > palette_buffer;