Shadow-mappping and post-processing

This implementation applies shadow-mapping and post-processing techniques.

Coordinate transformations, projections and vector calculations are used to simulate shadows in a basic geometric scene.

Post-processing techniques are also used to create various after effects.

The code follows examples outlined in:

• https://learnopengl.com/Advanced-Lighting/Shadows/Shadow-Mapping
• https://learnopengl.com/Advanced-OpenGL/Framebuffers

Changes over example code

• The ability to toggle shadowing effects.
• The ability to toggle post-processing effects.

Running the implementation

• Navigate the Solution Explorer to path:

  Solution -> 05.advanced_lighting -> 03.shadow_mapping_and_post_processing

• Left-click the project name and select Set as Startup Project from the pop-up window.

• Press F5 to run the project.

Interfacing with the implementation

Exiting

Press the ESC key to exit the implementation.

Movement

The movement key-bindings follow an FPS-style scheme:

• W move forward
• S move back
• A move left
• D move right
• Spacebar move up
• Left-Shift move down
• Mouse-movement look around the world.

Rendering manipulations

The numeric keys 1-3 are used to select shadow-mapping algorithms:

• 1 Toggle shadow-mapping (off by default): There will be a couple graphical anomalies (bugs) present initially. The anomalies can be removed by toggling the 2 and 3 keys detailed below.

  

• 2 Toggle shadow acne (on by default): One of the bugs inherent in the original shadow-mapping algorithm is called shadow-acne. The bug happens because of the discrete resolution of the depth buffer. The bug is resolved by adding an offset to each calculation.

  

• 3 Toggle Depth-averaging (off by default): The shadow-mapping algorithm with the shadow acne fix gives realistic results. However, a closer inspection reveals pixilated edges of the shadows. The effect can be mitigated by running an averaging algorithm around the edges of the shadows.

  

Keys 8, 9, i, o, p, k and l are used to select post-processing effects:

• 8 No post-processing filter: the scene is drawn without post-processing effects.

  

• 9 Edge detection filter: implemented like a sharpening filter, but more contrast is added between edges.

  

• 0 Emboss filter: an effect that makes details on flat surfaces seem raised.

  

• i Inversion filter: RGB colors in the scene are inverted.

  

• o Blur filter: edges are averaged and less defined.

  

• p Top-Sobel filter: an edge detection filter that emphasizes horizontal edges more than vertical edges.

  

• k Grayscale filter: RGB colors are averaged and converted to a black and white spectrum.

  

• l (lowercase "L") Sharpen filter: edges are more defined.