Update on PSX Shader Fog

Overview

In this update, made significant improvements to our PlayStation (PSX) shader. The primary enhancement is the addition of a fog effect, which helps replicate the classic look and feel of PSX-era games. This update affects both the OpenGL and DirectX versions of our shader.

Changes and Enhancements

1. Addition of Fog Effect

• Fog Density Parameter
  • New Property: FogDensity
  • Description: Controls the density of the fog effect applied to the scene.
• Implementation in OpenGL Shader
  • Vertex Shader:
    • Added a new varying variable depth to store the depth value.
    • Modified the w-component of the gl_Position to calculate the fog density.
    • Passed the depth value to the fragment shader.
  • Fragment Shader:
    • Used the depth value to calculate the fog effect.
    • Applied the fog effect by dividing the color by the depth value.
    • Ensured the fog effect does not exceed the original color values.
• Implementation in DirectX Shader
  • Vertex Shader:
    • Added a new output variable PositionW to store the position in homogeneous coordinates.
    • Modified the w-component of PositionW to include the fog density.
    • Passed the PositionW value to the fragment shader.
  • Fragment Shader:
    • Used the PositionW value to calculate the fog effect.
    • Applied the fog effect similarly by dividing the color by the depth value.
    • Ensured the fog effect does not exceed the original color values.

2. Improved Jitter Effect

• Jitter Parameter Adjustments
  • Adjusted the calculation and application of the jitter effect to enhance the visual artifacts, making them more in line with PSX graphics.
  • The jitter effect now scales with a smaller factor to better simulate the desired visual effect.