A vast amount of soft shadow map algorithms have been presented in recent years. Most use a single sample hard shadow map together with some clever filtering technique to calculate perceptually or even physically plausible soft shadows. On the other hand there is the class of much slower algorithms that calculate physically correct soft shadows by taking and combining many samples of the light....

16 June 1994 12:32 pm We describe a number of visual illusions of motion in depth in which the motion of an object's cast shadow determines the perceived 3D motion of the object. The illusory percepts are phenomenally very strong. We analyze the information which cast shadow motion provides for the inference of 3D object motion and experimentally measure human observers' use of this information...

Electrical contacts on the top surface of solar cells and light emitting diodes cause shadow losses. The phenomenon of extraordinary optical transmission through arrays of subwavelength holes suggests the possibility of engineering such contacts to reduce the shadow using plasmonics, but resonance effects occur only at specific wavelengths. Here we describe instead a broadband effect of enhance...

This paper proposes a new shadow map technique termed trapezoidal shadow maps to calculate high quality shadows in real-time applications. To address the resolution problem of the standard shadow map approach, our technique approximates the eye’s frustum as seen from the light with a trapezoid to warp it onto a shadow map. Such a trapezoidal approximation, which may first seem straightforward, ...

We propose an efficient and light-weight solution for rendering smooth shadow boundaries that do not reveal the tessellation of the shadow-casting geometry. Our algorithm reconstructs the smooth contours of the underlying mesh and then extrudes shadow volumes from the smooth silhouettes to render the shadows. For this purpose we propose an improved silhouette reconstruction using the vertex nor...

Shadow maps are a widely used means for the generation of shadows although they exhibit aliasing artifacts and problems of numerical precision. In this paper we extend the concept of a single shadow map by introducing dual shadow maps, which are based on the two depth layers that are closest to the light source. Our shadow algorithm takes into account these two depth values and computes an adap...

Author Samuli Laine Title Efficient Physically-Based Shadow Algorithms This research focuses on developing efficient algorithms for computing shadows in computer-generated images. A distinctive feature of the shadow algorithms presented in this thesis is that they produce correct, physicallybased results, instead of giving approximations whose quality is often hard to ensure or evaluate. Light ...

Forward shadow mapping is a new approach to real-time shadow generation. The traditional shadow map algorithm maps the pixels in the eye's view backward into the depth buuers of light sources (i.e. shadow maps), which is similiar to and often implemented as an extension to texture mapping. Our algorithm reverses this process by using 3-D image warping techniques to transform shadow map pixels f...

A shadow appears on an area when the light from a source cannot reach the area due to obstruction by an object. The shadows are sometimes helpful for providing useful information about objects. However, they cause problems in computer vision applications, such as segmentation, object detection and object counting. Thus shadow detection and removal is a pre-processing task in many computer visio...