Summary
When content is authored-scaled down to an extreme factor (example: 0.01×), the rendered result looks as if all geometry is snapped/quantized to the device pixel grid (blocky / “pixel snapped” appearance). However, when scaling back up (e.g. 100× or 101×), the result becomes visually identical to the original design, which suggests the authored values are not permanently modified—this appears to be a renderer behavior at small effective geometry sizes.
This is especially noticeable when the downscaled scene still occupies a small but non-trivial device-space area (e.g. ~10×21px in the screenshot), where many independent shapes appear to collapse/align to the same pixel grid.
Expected behavior
Scaling authored geometry down should produce a visually consistent rasterization of the same design at that scale:
- subpixel geometry should be handled via normal coverage / anti-aliasing rules
- shapes shouldn’t “snap” to a coarse pixel grid as if their positions/sizes were quantized
Actual behavior
At extreme authored downscales (e.g. 0.01×):
- the output looks pixel-snapped/quantized, affecting even simple filled rectangles (not just strokes)
- scaling back up restores the original look (suggesting the problem is not from the authored model, but from rendering at tiny effective sizes)
Reproduction notes / evidence
- The issue reproduces with simple rect geometry (not dependent on strokes).
- Attached screenshots show the effect clearly under “ISSUE HERE”.
Skia sanity check
A minimal skia-safe reproduction indicates Skia itself does not “force tiny rects to 1px” in a simple way:
- A 0.1×0.1 rect on a 1×1 surface with AA off can produce no coverage
- With AA on, it produces partial coverage
- If the canvas is scaled such that the rect becomes 1×1 in device space, the pixel becomes fully covered
This suggests the observed snapping is more likely due to the rendering pipeline / transforms / caching / bounds decisions rather than a basic Skia limitation.
Why this matters
This breaks visual fidelity for workflows that rely on “authoring-time scale” (baking scale into geometry/props). Users expect:
- extreme downscale to look like a small version of the same design (even if it becomes hard to see)
- zooming back in to reveal a faithful miniature rendering, not a snapped/quantized one
Possible directions (non-prescriptive)
Potential areas to inspect:
- any float→int conversions, snapping, or “minimum device pixel” logic in the renderer
- picture/layer recording bounds and clip/saveLayer bounds behavior at tiny scales
- any caching logic that rasterizes at small sizes and reuses results
original, left, scaled 0.01x, then 100x back, right.
0.01x scaled version of the original. (wrong)
Summary
When content is authored-scaled down to an extreme factor (example: 0.01×), the rendered result looks as if all geometry is snapped/quantized to the device pixel grid (blocky / “pixel snapped” appearance). However, when scaling back up (e.g. 100× or 101×), the result becomes visually identical to the original design, which suggests the authored values are not permanently modified—this appears to be a renderer behavior at small effective geometry sizes.
This is especially noticeable when the downscaled scene still occupies a small but non-trivial device-space area (e.g. ~10×21px in the screenshot), where many independent shapes appear to collapse/align to the same pixel grid.
Expected behavior
Scaling authored geometry down should produce a visually consistent rasterization of the same design at that scale:
Actual behavior
At extreme authored downscales (e.g. 0.01×):
Reproduction notes / evidence
Skia sanity check
A minimal
skia-safereproduction indicates Skia itself does not “force tiny rects to 1px” in a simple way:This suggests the observed snapping is more likely due to the rendering pipeline / transforms / caching / bounds decisions rather than a basic Skia limitation.
Why this matters
This breaks visual fidelity for workflows that rely on “authoring-time scale” (baking scale into geometry/props). Users expect:
Possible directions (non-prescriptive)
Potential areas to inspect:
original, left, scaled 0.01x, then 100x back, right.
0.01x scaled version of the original. (wrong)