A GPU-Based Approach to Non-Photorealistic Rendering in the Graphic Style of Mike Mignola

The subject of Non-Photorealistic Rendering (NPR) is one which tends towards a certain, small set of targeted appearances. Work in NPR in particular in real-time graphics is generally aimed at a classic cel-animated, "cartoon" visual style that is, solid black outlines with clamped ramp shading. While this look is often arresting and interesting, it is a narrow approach to NPR. Even within the bounds of a "cartoony" style, significant variations can be found. Of particular interest is the art of illustrator Mike Mignola, popularized in his Hellboy comic book series. We present a method for rendering a pre-built model in the style of Mignola’s illustration. GPU acceleration is used to funnel large numbers of geometry-based edges, without a huge performance drop. Vertex Buffer Objects (VBOs) are used to create strokes along the outside edge of geometry, and along the edges of shadows.