Doffy

Purescript based canvas rendering framework.

Note: I am in the process of extracting the library from one of my side projects. At the moment this repo only contains a small part of it.

Notable features include:

• FRP based rendering with TEA-like actions
• svg-like event listeners
• flexbox-inspired layouting system
• multi-step rendernig, where one step can query metadata collected from previous steps:
  • local transform matrices
  • geometries
  • relative & absolute bounds

As a testament to the extensability of the library, both the Padding and the Flex components have been implemented without adding any new branches to the Geometry adt.

Planned features

• layers: at the moment each render step represents a layer. I would to support layers nested down a larger tree.
• multi-canvas rendering: display data on more than one canvas for minimal re-renders
• hover-events (eg: onhoverstart, onhoverend). Right now hovering is pull based (the programmer asks the library what is curently being hovered over)

Would be nice to have, no idea if I will ever get to it

• chrome extension adding a geometry inspector
• multiple back ends (svg, webgl, etc)

Development

Building the package

spago build

Running the test suite

spago -x ./spago.test.dhall test

If you think a particular helper would be an useful addition, feel free to open an issue.