Tilesets

[mariovisic]

A tileset implementation

TODO:

• Complete the code for openGL ES, 1.2 and 1.3
• Add commenting documentation to the code
• Fix code formatting / consistency with existing ruby2d code
• Add ability to set width/height of the original tileset, to scale the tile size, same how sprites work
• Add ability to rotate tiles (same as sprites)
• Add ability to mirror tiles (same as sprites)
• Look into performance of the code, we may need to pre-render out the tiles when they're defined, rather than currently we render the entire image for every tile and then crop what we need, this may be slow for large tilesets.
• Add a way to remove or clear all set tiles
• Add direct draw code

[mariovisic]

A note on performance, I tested an extreme case with a 1024 x 576 window size, using a large 4032 × 3024 tileset image. I Then selected a random 100 16x16 tiles, to use and filled the entire 1024x576 window with tiles, so 2304 tiles in total.

On my M1 laptop I see around ~ 44% CPU usage from the process and ~ 31% GPU usage shown in activity monitor. This seems 'acceptible' as it should still hit 60fps on a machine half as powerful in an extreme case (i'd expect a typical tileset to be smaller and tiles to be larger). but performance could definitely be improved by avoiding rendering the entire image each time.

[mariovisic]

Code to test performance:

require 'ruby2d'

GRID_SIZE = 16

set background: 'white'
set width: GRID_SIZE * 64
set height: GRID_SIZE * 36

tileset = Tileset.new('/path/to/very/large/image.jpeg', tile_width: GRID_SIZE, tile_height: GRID_SIZE, padding: 0, spacing: 0)

100.times { |i| tileset.define_tile(i.to_s, rand(252),rand(189)) }

64.times do |i|
  36.times do |j|
    tileset.set_tile(rand(100).to_s, [
      {x: GRID_SIZE * i,  y: GRID_SIZE * j}
    ])
  end
end

show

[blacktm]

On a performance note, we actually haven’t implemented batch rendering for textures yet (here’s what it looks like for triangles), so that should dramatically speed things up when we do through reduced draw calls.

[mariovisic]

Output from test/tileset.rb: 😂

The numbers aren't exactly the same size so this output is expected 👌