Implementations of the present disclosure are directed to a method, a system, and an article for rendering shadows in a graphical image of a virtual environment. An example computer-implemented method can include: generating a digital image of a virtual environment; providing a depth buffer for the digital image that includes a depth value for each pixel in the digital image; rendering a first shadow in a first region of the digital image by, at least, adjusting colors and depth values for pixels in the first region; and rendering a second shadow in a second region that partially overlaps the first region by, at least: (i) identifying a shadow rendering region to be within the second region but outside the first region, based on the adjusted depth values; and (ii) adjusting colors and depth values for pixels in the shadow rendering region.