Raycaster Engine

This projects tries to reimplement the 2.5D Graphics technique in games like Wolfenstein. These class of games us a 2D grid combined with raycasting to draw cubes where the wall height is related to the distance to the player.

Current Features:

• Textured walls and floors using tile-map
• Multi-textured walls depending on side
• Sprites
  • Transparent Sprites
  • Directional Sprites for a "3D" effect
  • Simple Animations
• Doors (Thin Wall)
• Keyboard and Mouse Controls
• Looking up and down
• Transparent Walls & Doors

Future Features:

• Better way to design and load map data
• Proper Fog (Might mix with lighting in some way)
  • If we know the fog will block walls/sprites, we can simply not render them as well
• Multiple Levels (requiring multiple raycasting passes for each)

Small Fixes:

• Render the sides of transparent walls, or add option too
• Use simple shading for walls based on the side
• Fix mouse control
• Add player height control option
• Fix map system to have 1MAP = 0TEXID and so on

Possible Optimizations

• Build a render_item struct hold only the data needed to render (texCol, perpDist, column, Texture*)
  • We can then eliminate the multi-wall and door_texcol calculations from the render loop
• move from AOS to SOA
• create an arena to pack booleans instead of using uint8_t which wastes 7 bits
• Write to the pixel buffer as rows and transpose at the end. Common case of writing down a column is not cache performant

Other possible ideas:

• Vertically Opening doors (could just use tranparent texture animations)
• Lighting System
• Floors/Ceiling slabs, depth
• Moving Walls
  • Horizontal requires new non-cubic wall intersection check
  • Vertical walls require rendering ceiling slabs so the bottom of the wall is solid
• Mirrors/Portals (raycasting aspect is fine but to render the floor and sprites from the portals POV requires redoing a modified render pass for each portal)