Hardware accelerated real time charcoal rendering

Abstract

In this paper, we present simple rendering techniques implemented using traditional graphics hardware to achieve the effects of charcoal drawing. The effects include characteristics of charcoal drawings like broad grainy strokes and smooth tonal variations that are achieved by smudging the charcoal by hand. Further, we also generate the closure effect that is used by artists at times to avoid hard silhouette edges. All these effects are achieved using contrast enhancement operators on textures and/or colors of the 3D model.Our contribution lies in unifying the methods to achieve these effects under the common framework of contrast enhancement operators. Further, since the effects have been implemented using traditional graphics hardware, a single rendering pass is sufficient to create different effects. Hence, we can render highly complex models with large number of triangles at interactive rates. Thus, our method is especially suited for applications like scientific visualization and preliminary sketches/animations.

Integrated shadow removal based on photogrammetry and image analysis

“…They generally belong to or are close to the upper cut-off of the shadow area, and become very bright after restoration. This edge effect is reduced by smudging (Majumder and Gopi 2002). Integrated shadow removal 3923…”

Hardware-Accelerated Sumi-e Painting for 3D Objects

“…Majumder [8] implemented real-time charcoal rendering applied with contrast enhanced operators by using hardware-accelerated bump mapping and Phong shading. Lake [6] presented a method for cartoon rendering suits for programmable pipeline.…”

Simulating wax crayons

“…Graphical primitives are interpreted as artistic strokes or patches made by the simulated artistic medium. Previous work simulated media such as pencil sketches [20,7] and drawings [13,15,21], charcoal drawings [14], watercolour [5], and stained glass [16]. Also, some work tries to simulate particular artistic styles, such as those of Dr. Seuss and Geoffrey Hayes [11].…”