Screen space ambient occlusion (SSAO) is a technique in real-time rendering for approximating amount by which a point on a surface is occluded by surrounding geometry, which helps in adding soft shadows to diffuse objects. Most of the current methods use the depth buffer as an approximation to scene geometry to sample the occlusion factor. We introduce a novel technique which uses a partial representation of the scene (here triangle information in screen space) using compact triangle storage and a ray-marching approach to find a better approximation of the occlusion factor.