Glow effects simulate the characteristics of a lens that suffers from light bleeding due to a high dynamic range. In photography, most cameras are set to use an average metering algorithm. The camera will analyze the frame and take the average exposure as the midpoint. Anything outside the camera... Read more »

When light bounces off a surface, it contributes to the amount of ambient lighting, or environment lighting we see. In a basic renderer, the amount of ambient lighting a surface receives is uniform, making it look rather flat. Ambient occlusion provides a more realistic shading technique by takin... Read more »

Refraction is the bending of light when passing from one medium into another. When light reaches your eyes, the objects appear bent or distorted in some way. You see this type of physical property whenever you stare at objects within water or when you look off to the horizon on a hot day and see ... Read more »

When compositing two or more images, you mix them together using some sort of blend operation. The common blending operation is to mix the foreground onto the background taking into account the alpha channels between the two. Read more »

When you view an image on your monitor, the RGB pixels that make up the image are altered in such a way to better accommodate human vision. Human vision is more sensitive to shadows then it is for midtones or highlights. Hardware manufactures account for this nonlinear behaviour by applying a pow... Read more »

Depth of field (abbr. DOF) is a region where subjects appear to be in focus. When a subject moves away from the point of focus, it begins to defocus or blur due to the physical nature of how light interacts with lenses (including your eyes) and projects an object onto a screen. Read more »

Shadow mapping is a hardware accelerated technique for casting shadows in a 3D scene. It has become the industry standard method for casting shadows due to its simplicity, its rendering speed, and its ability to produce soft shadows. This article will go over the shadow mapping technique as well ... Read more »

The purpose of this interactive shader is to demonstrate how you can use sepia toning, noise, film scratches, and vignetting to produce a classic looking film effect. This is a post-process effect, so you render your scene normally to a texture using a fragment buffer object and then operate on t... Read more »

As the first in a series of articles about popular shader effects, this article goes over the basics of 3D lighting through an interactive WebGL demo. You'll learn about the lighting formula using ambient, diffuse and specular reflection, light attenuation, and spotlight effects. This article wil... Read more »