Adding other 2 methods used for shadow comparison

Author: lquatrin

README.md

@@ -36,6 +36,19 @@ A volume rendering application with different techniques, trying to be as simila
   - Leonardo Q. Campagnolo, Waldemar Celes. Interactive directional ambient occlusion and shadow computations for volume ray casting. Computers & Graphics, Volume 84, 2019, Pages 66-76, ISSN 0097-8493. doi: 10.1016/j.cag.2019.08.009.
   - Links: [Elsevier](https://www.sciencedirect.com/science/article/abs/pii/S0097849319301372)
 
+* 1-Pass - Ray Casting - Extinction-based
+  - Structured Single-pass Ray Casting: Extinction-based shading
+  - Schlegel, P, Makhinya, M, Pajarola, R. Extinction-based shading and illumination in gpu volume ray-casting. IEEE Transactions on Visualization and Computer Graphics 2011 Dec;17(12):1795–1802. doi: 10.1109/TVCG.2011.198.
+  - Links: [IEEE](https://ieeexplore.ieee.org/document/6064942)
+  - Missing: Ambient Occlusion with Color Bleeding
+  - Summed Area Table (SAT) built with extinction coefficient (on CPU).
+
+* 1-Pass - Ray Casting - Voxel Cone Tracing
+  - Single-GPU version implemented just for render comparison
+  - Structured Single-pass Ray Casting: Voxel Cone Tracing Shadows
+  - Shih, M., Rizzi, S., Insley, J.A., Uram, T.D., Vishwanath, V., Hereld, M., Papka, M.E., & Ma, K. (2016). Parallel distributed, GPU-accelerated, advanced lighting calculations for large-scale volume visualization. 2016 IEEE 6th Symposium on Large Data Analysis and Visualization (LDAV), 47-55. doi: 10.1109/LDAV.2016.7874309.
+  - Links: [IEEE](https://ieeexplore.ieee.org/document/7874309)
+
 * Slice-based - Directional Occlusion
   - Structured Slice-based Texture Mapping: Directional Occlusion Shading Model
   - Schott, M., Pegoraro, V., Hansen, C., Boulanger, K. and Bouatouch, K. (2009), A Directional Occlusion Shading Model for Interactive Direct Volume Rendering. Computer Graphics Forum, 28: 855-862. doi:10.1111/j.1467-8659.2009.01464.x.

cppvolrend/CMakeLists.txt

@@ -40,6 +40,13 @@ add_executable(cppvolrend
                structured/rc1pdosct/conegaussiansampler.cpp                    structured/rc1pdosct/conegaussiansampler.h
                structured/rc1pdosct/dosrcrenderer.cpp                          structured/rc1pdosct/dosrcrenderer.h
                structured/rc1pdosct/extcoefvolumegenerator.cpp                 structured/rc1pdosct/extcoefvolumegenerator.h
+              
+               # Extinction-based shading to compute ambient occlusion and cone shadows with Summed Area Table
+               structured/rc1pextbsd/ebsrenderer.cpp                           structured/rc1pextbsd/ebsrenderer.h
+               
+               # Voxel Cone Tracing to compute Shadows (Single GPU version)
+               structured/rc1pvctsg/preprocessingstages.cpp                    structured/rc1pvctsg/preprocessingstages.h
+               structured/rc1pvctsg/vctrenderer.cpp                            structured/rc1pvctsg/vctrenderer.h
 
                # Directional Occlusion Shading for GPU Slice/Texture-based 
                structured/sbtmdos/sbtmdosrenderer.cpp                          structured/sbtmdos/sbtmdosrenderer.h

cppvolrend/main.cpp

@@ -23,6 +23,8 @@
 #include "structured/rc1pass/rc1prenderer.h"
 #include "structured/rc1pcrtgt/crtgtrenderer.h"
 #include "structured/rc1pdosct/dosrcrenderer.h"
+#include "structured/rc1pextbsd/ebsrenderer.h"
+#include "structured/rc1pvctsg/vctrenderer.h"
 // Slice based
 #include "structured/sbtmdos/sbtmdosrenderer.h"
 //-----------------------------------------------------------------------------------------------------------------------------------------------------------------
@@ -57,6 +59,8 @@ int main (int argc, char **argv)
   RenderingManager::Instance()->AddVolumeRenderer(new RayCasting1Pass());
   RenderingManager::Instance()->AddVolumeRenderer(new RC1PConeLightGroundTruthSteps());
   RenderingManager::Instance()->AddVolumeRenderer(new RC1PConeTracingDirOcclusionShading());
+  RenderingManager::Instance()->AddVolumeRenderer(new RC1PExtinctionBasedShading());
+  RenderingManager::Instance()->AddVolumeRenderer(new RC1PVoxelConeTracingSGPU());
   //-----------------------------------------------------------------------------------------------------------------------------------------------------------------
   // Slice based
   RenderingManager::Instance()->AddVolumeRenderer(new SBTMDirectionalOcclusionShading());