Fixed rectangle drawing, at long last. ¦D
Merge branch 'core'
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.
WIP: Shader macro system.