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This chapter will go over some of the basic rendering tools and how to use them.

In order to get anything to render, you will need to spawn a window, and a camera that outputs to it.

window <- spawn Window
spawn_ (Camera, Rel OutputTo window)

The window can be given a title using WindowTitle, a size using WindowSize and flags using WindowFlags. You can find more info in Mischief.SDL.Window.

Each camera has a CameraTexture component containing its texture. A view to the texture can be obtained using cameraView. Alternatively, cameraSwapView will give you the view while swapping the actual camera's texture to a secondary one, so that you can both read and output to it at the same time.

In order to spawn a sprite you need to give it the entity of an Image asset. You also need to provide it a material.

img <- load @Image "foo.png"
spawn_ (Sprite img, WithMaterial @SpriteMaterial)

Sprites accept all forms of transform manipulation: movement, rotation, scaling.

-- rotating all sprites by 0.2
query_ $ do
  (entity, transform) <- [q|Entity, Transform / With Sprite|]
  qlift $ insert (Transform.rotateZ 0.2) entity

You can insert a custom SpriteSlice to make the sprite only a slice of its texture:

insert (SpriteSlice (V2 30 0) (V2 50 50))

You can set a custom SpriteFlip to flip the sprite horizontally or vertically:

insert (SpriteFlip {x = True, y = False}) sprite

Internally, the information from all these components is uploaded into a SpriteData buffer on each entity, which is bound to the materials extending SpriteMaterial. It is then used when calling sampleSprite.