A system and method for increasing resolution of an object and increasing rendering speed by rendering with a lesser density for non-object regions. The system and method includes sampling a plurality of first rays in a first density through a volume, each first ray being in a separate section, if a sampling value difference of at least two first rays is above a first threshold, sampling a plurality of second rays in a second density, the second rays being in a first section of the separate sections, the first section being for one of the at least two first rays, and if a sampling value difference between a first one of the second rays and another ray is above a second threshold, sampling a plurality of third rays in a second section spatially different than the first section, the sampling of the third rays being at the second spatial density and the second section being a neighboring section to the first section.