Skip to content

Always use SVG mipmaps that match or exceed the skins' screen-space size #649

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Aug 4, 2020
Merged

Always use SVG mipmaps that match or exceed the skins' screen-space size #649

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
26988e3
Clean up SVGSkin
adroitwhiz Jan 30, 2020
0d86ec9
Don't blur vector skins
adroitwhiz May 20, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
28 changes: 11 additions & 17 deletions src/SVGSkin.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ const Skin = require('./Skin');
const SvgRenderer = require('scratch-svg-renderer').SVGRenderer;

const MAX_TEXTURE_DIMENSION = 2048;
const MIN_TEXTURE_SCALE = 1 / 256;

/**
* All scaled renderings of the SVG are stored in an array. The 1.0 scale of
* the SVG is stored at the 8th index. The smallest possible 1 / 256 scale
Expand Down Expand Up @@ -118,26 +118,20 @@ class SVGSkin extends Skin {
// The texture only ever gets uniform scale. Take the larger of the two axes.
const scaleMax = scale ? Math.max(Math.abs(scale[0]), Math.abs(scale[1])) : 100;
const requestedScale = Math.min(scaleMax / 100, this._maxTextureScale);
let newScale = 1;
let textureIndex = 0;

if (requestedScale < 1) {
while ((newScale > MIN_TEXTURE_SCALE) && (requestedScale <= newScale * .75)) {
newScale /= 2;
textureIndex -= 1;
}
} else {
while ((newScale < this._maxTextureScale) && (requestedScale >= 1.5 * newScale)) {
newScale *= 2;
textureIndex += 1;
}
}
// Math.ceil(Math.log2(scale)) means we use the "1x" texture at (0.5, 1] scale,
// the "2x" texture at (1, 2] scale, the "4x" texture at (2, 4] scale, etc.
// This means that one texture pixel will always be between 0.5x and 1x the size of one rendered pixel,
// but never bigger than one rendered pixel--this prevents blurriness from blowing up the texture too much.
const mipLevel = Math.max(Math.ceil(Math.log2(requestedScale)) + INDEX_OFFSET, 0);
// Can't use bitwise stuff here because we need to handle negative exponents
const mipScale = Math.pow(2, mipLevel - INDEX_OFFSET);

if (this._svgRenderer.loaded && !this._scaledMIPs[textureIndex + INDEX_OFFSET]) {
this._scaledMIPs[textureIndex + INDEX_OFFSET] = this.createMIP(newScale);
if (this._svgRenderer.loaded && !this._scaledMIPs[mipLevel]) {
this._scaledMIPs[mipLevel] = this.createMIP(mipScale);
}

return this._scaledMIPs[textureIndex + INDEX_OFFSET] || super.getTexture();
return this._scaledMIPs[mipLevel] || super.getTexture();
}

/**
Expand Down