Parallax Voxel Ray Marcher

Project in High Performance Computer Graphics (3rd place) at LTH by Theodor Lundqvist, Jiuming Zeng and Jintao Yu.

Video: https://youtu.be/21KFuvCqHIU (8000+ views)

Paper: Parallax Voxel Ray Marcher.pdf

                         

Some personal notes:

GRID TRAVERSAL

voxel traversal using FVTA algorithm http://www.cse.yorku.ca/~amana/research/grid.pdf

MODELS

Models can be converted from mesh to voxel grid using online resources https://github.com/davidstutz/mesh-voxelization https://drububu.com/miscellaneous/voxelizer/?out=obj

voxel ray marching techniques

how Teardown does it: https://www.youtube.com/watch?v=0VzE8ROwC58

distance fields - can be made fast on gpu but still slower it seems https://www.youtube.com/watch?v=REKcTBgkrsE

parallax voxel raymarching https://www.youtube.com/watch?v=h81I8hR56vQ

atomotage engine

• https://www.youtube.com/watch?v=nr5JqYYye3w
• https://www.youtube.com/watch?v=4AYBm-9cBqs
• https://www.youtube.com/watch?v=1sfWYUgxGBE

moving voxelvolumes around and intersecting.

Have to disable early depth test since depth can change in fragment shader. Though we can use an extension: https://www.khronos.org/opengl/wiki/Fragment_Shader#Conservative_Depth

layout (depth_less) out float gl_FragDepth;

To say that we always will move the pixel closer than the plane it was rendered on, which is the only thing we will do when rendering backfaces

cool examples: https://www.shadertoy.com/view/cdsGz7 https://www.shadertoy.com/view/dtVSzw https://www.shadertoy.com/view/tdlSR8