When two triangles share an edge, we need to decide which triangle draws that edge. The standard approach is to draw the top and left edges.
Implementing the top-left rule ensures rasterisation is consistent, whichever order triangles are drawn in.
See Triangle rasterization (Wikipedia)
When two triangles share an edge, we need to decide which triangle draws that edge. The standard approach is to draw the top and left edges.
Implementing the top-left rule ensures rasterisation is consistent, whichever order triangles are drawn in.
See Triangle rasterization (Wikipedia)