The document discusses faster particle rendering using DirectCompute. It describes using the GPU for particle simulation by taking advantage of its parallel processing capabilities. It discusses using compute shaders to simulate particle behavior, handle collisions via the depth buffer, sort particles using bitonic sort, and render particles in tiles via DirectCompute to avoid overdraw from large particles. Tiled rendering involves culling particles, building per-tile particle indices, and sorting particles within each tile before shading them in parallel threads to composite onto the scene.