A shader could only be judged by placing it on a sprite and running
the scene. The shader tab now shows its effect next to the graph, on
the image the user picked last, without a picker to maintain.
- The preview follows the last selection that has an image: a placed
sprite with its overrides, size and tint, a sprite asset, a texture
or a frame. Clicking the shader, a node, a behavior or a scene keeps
the picture.
- Without such a selection, or when the picked image is deleted, a
built-in 64 px test image is shown. Its colour runs with u and v, a
checkerboard shows where a UV lands and the border fades for alpha.
- Each property gets a slider. The sliders belong to the preview and
never write to the project. They start at the sprite's values when
it carries this shader, otherwise at the default.
- The preview has its own clock. Hold and Restart are only enabled
when a Time node is in the graph.
- The graph | splitter | panel layout of the particles tab moves into
PreviewSplit, and both tabs use it.
- A nine-sliced frame is previewed unsliced. This is documented.
Findings:
- The slider row stayed squeezed to a few pixels when the properties
changed while the tab was hidden. The layout was triggered one level
too high. The slider check in block 28n holds this.
- The graph canvas is narrower now, 385 px at a 1280 px window, the
same as in the particles tab. Block 28b clicked at a fixed x+420 and
now uses the measured width.
Tests:
- ./check.sh: 132 files, 1952 tests (was 131 / 1941), exit 0
- npm run build: exit 0
- GM_STEPS=28,31 freshly seeded: ALL PASSED, 105 checks
- 11 new unit tests in tests/editor/shader-preview.test.ts
- 7 new e2e checks in block 28n
- Counter-probes: start values ignoring the sprite fail 1 unit test,
a preview ignoring the selection fails 2 e2e checks
- Check total 1209 in README is computed (1202 + 7), CI measures it
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
