skia2/experimental/canvaskit/helper.js
Kevin Lubick 1a05fceb38 [canvaskit] Expand canvas2d API
Made addPath take one more arg to allow for append/expand
(which makes emulating the HTML canvas easier).

Add Gold test for various lineTo/pathTo, etc.

Make CanvasKit.Color() choose a better value for alpha
when omitted (was 0, should be 1).

Add some parsing logic to deal with colors/font sizes.
Fonts are going to be rather complex it seems.

Moves some arc-related logic to the JS side, (although
this should preserve the behavior of CanvasKit.arc() to
behave like the Canvas implementation)

Make Examples and tests to a side-by-side comparison to
HTML canvas where applicable.

Add a Changelog for PathKit.  There was a bug (I thought), but
turns out I was wrong.  The Changelog will be for future
bug fixes.

Bug: skia:
Change-Id: I1bd603fdb518232604b098e24543e3453015b504
Reviewed-on: https://skia-review.googlesource.com/c/170446
Reviewed-by: Kevin Lubick <kjlubick@google.com>
2018-11-20 18:39:43 +00:00

20 lines
735 B
JavaScript

// Adds any extra JS functions/helpers we want to add to CanvasKit.
// Wrapped in a function to avoid leaking global variables.
(function(CanvasKit){
function clamp(c) {
return Math.round(Math.max(0, Math.min(c || 0, 255)));
}
// Colors are just a 32 bit number with 8 bits each of a, r, g, b
// The API is the same as CSS's representation of color rgba(), that is
// r,g,b are 0-255, and a is 0.0 to 1.0.
// if a is omitted, it will be assumed to be 1.0
CanvasKit.Color = function(r, g, b, a) {
if (a === undefined) {
a = 1;
}
return (clamp(a*255) << 24) | (clamp(r) << 16) | (clamp(g) << 8) | (clamp(b) << 0);
}
}(Module)); // When this file is loaded in, the high level object is "Module";