We present a hybrid algorithm for rendering hard shadows accurately and efficiently. Our method combines the strengths of shadow maps and shadow volumes. We first use a shadow map to identify the pixels in the image that lie near shadow discontinuities. Then, we perform the shadow-volume computation only at these pixels to ensure accurate shadow edges. This approach simultaneously avoids the ed...

In urban areas, the presence of shadow in high resolution satellite images is caused a serious problem for the full exploitation of images. To solve the shadow problem in high resolution satellite images, this paper propose a new shadow detection and reconstruction algorithm. Mainly three stages are using in this paper shadow detection stage, training stage and shadow reconstruction stage. The ...

We present a review on rendering rigid shadows precisely and proficiently. Our review provides the details of all the existing methods for rendering shadows and the hybrid approaches. Hybrid approaches merge the two or more existing algorithms. The algorithm merges shadow map and shadow volume computation. Analysis of shadow volume, shadow map and projection algorithm is performed and is mentio...

We present a method for high quality soft shadows for area lights in cinematic lighting. The method is an extension of traditional shadow maps, so it has the advantage of image based shadow methods; the algorithm’s complexity is independent of geometric complexity. We introduce multilayer transparent shadow maps, which can be used to produce high quality soft shadows for scenes with extremely c...

We present Convolution Shadow Maps, a novel shadow representation that affords efficient arbitrary linear filtering of shadows. Traditional shadow mapping is inherently non-linear w.r.t. the stored depth values, due to the binary shadow test. We linearize the problem by approximating shadow test as a weighted summation of basis terms. We demonstrate the usefulness of this representation, and sh...

In the large-scale terrain scene rendering, because of the complexity of the shadow algorithm, the algorithm of the real-time shadow have not been able to achieve satisfactory rate. In this situation, this paper proposed a GPU-based real-time shadow algorithm. It can be used for generating real-time shadow effect in morphing terrain rendering. First of all, this method pre-processes terrain dat...

Given a set of n non-overlapping unit disks in the plane, a line ` is called blocked if it intersects at least one of the disks and a point p is called a shadow point if all lines containing p are blocked. In addition, a maximal closed set of shadow points is called a shadow region. We derive properties of shadow regions, and present an O(n) algorithm that outputs all shadow regions. We prove t...

Shadows cause problems in image processing. In this paper, a new methodology for shadow removal based on Strong Edge Detection (SED) method is proposed. The strong shadow edges are recognized by learning the patch based characteristics of shadow edges and then image features are analyzed to guide a Shadow Edge Classifier. Also, spatial patch smoothing is used to enforce uniformity between adjac...

Rendering high-quality shadows in real-time is a challenging problem. Shadow mapping has proved to be an efficient solution, as it scales well for complex scenes. However, it suffers from aliasing problems. Filtering the shadow map alleviates aliasing, but unfortunately, native hardware-accelerated filtering cannot be applied, as the shadow test has to take place beforehand. We introduce a simp...

Shadow maps are a very efficient means to add shadows to arbitrary scenes. In this paper, we introduce Translucent Shadow Maps, an extension to shadow maps which allows very efficient rendering of sub-surface scattering. Translucent Shadow Maps contain depth and incident light information. Sub-surface scattering is computed on-the-fly during rendering by filtering the shadow map neighborhood. T...