rasterizer

A small triangle rasterizer with a depth buffer.

Build

Build using CMake.

The code has been tested using gcc on Linux and Windows. The code is written in C++98.

A small overview

The rasterizer uses edge equations to quickly test whether a pixel is in the triangle or not. Values defined at the vertices can be interpolated across the triangle face.

• all the rasterization logic is in src/rasterizer.cpp
• a bounding box is computed for the triangle, and only pixels within the bounding box are tested.
• many unnecessary calculations are moved out of the rasterization loop. For instance, evaluating which half-plane the pixel is in requires the calculation of f(x, y) = A(x - x0) + B(y - y0). We can move this calculation out of the loop and replace it with a single addition by using the property f(x+1, y) - f(x, y) = A, and f(x, y+1) - f(x, y) = B.