US 8,411,089 B2 · Computer graphics method for creating differing fog effects in lighted and shadowed areas

Abstract

A method for providing fog or fading due to atmospheric effects during computer animation of an image. The method includes determining a lighting value for a scene's or an image's pixels based on the positions of the pixels relative to a light source. The method includes, for each of the pixels, setting a fade in start distance for each pixel measured from a camera location so as to define when fog is added, e.g., when to fade a pixel's color by blending this color with a fog color. The fade in start distances are set based on each pixel's lighting value, whereby pixels with smaller lighting values or shadowed pixels begin to fade first while highlighted pixels fade with greater distances. The method includes adding fog to the image starting at the fade in start distances for each of the pixels and then rendering the image.

Claims20

Dependent claims

A method for providing a fog effect during computer animation of an image, comprising:

with a fog effect module run by a processor of graphics system, determining a lighting value for each pixel of an image to be animated based on a location of each of the pixels relative to a light source;
with the fog effect module, setting for each of the pixels a fade in start distance measured from a camera location at which to start adding fog, wherein the fade in start distances are each selected based on the determined lighting value associated with a corresponding one of the pixels;
with the fog effect module, adding fog to the image including starting at the fade in start distances for each of the pixels;
and
with the graphics system, rendering the image using the fog-added pixels.

2 more elements

A computer program product, comprising:

a non-transitory computer useable medium and computer readable code embodied on the computer useable medium for simulating atmospheric effects in an animated image generated by a graphics system, the computer readable code comprising:
computer readable program code devices causing a computer to determine, for each of a plurality of pixels of an image, a distance from a camera location;
computer readable program code devices causing the computer to determine, for each of the pixels, a lighting value defining an amount of lighting of each of the pixels by a light source used to provide light in the image;
computer readable program code devices causing the computer, for each of the pixels, to blend a contribution of a pixel color and a contribution of a fog color to add fog to the image, wherein the contributions of the pixel color and the fog color are determined based on the lighting values and the camera distances;
and
computer readable program code devices causing the computer to render the image using the blend of the pixel color and the fog color contributions for each of the pixels.

3 more elements

A graphics system for generating animated images including a fog effect that is provided first in shadowed areas, comprising:

a memory device storing a plurality of image pixels, a color associated with each of the pixels, and a fog color;
a processor accessing the memory device and rendering an image;
and
a fog effect component run by the processor that uses a lighting value associated with each of the pixels to define a fade in start distance from a camera location and a fade in end distance from the camera location,
wherein the fade in start and end distances vary for the pixels such that the pixels with smaller lighting values have smaller fade in start and end distances than the pixels with larger lighting values,
wherein the fog effect component, for each of the pixels, blends the fog color with the pixel color to add a fog effect, with the contribution of the fog and pixel colors being selected based on a comparison of a camera distance for the pixel with the defined fade in start and end distances, and
wherein the rendering of the image by the processor is performed using the blended fog and pixel colors for each of the pixels.

4 more elements

Dependencies are inferred from the claim text.

Computer graphics method for creating differing fog effects in lighted and shadowed areas

Life of this patent

Computer graphics method for creating differing fog effects in lighted and shadowed areas

Life of this patent

Abstract

Claims20