Bitmap paint order — implementation reference

This section documents ImageCreator.drawImageBitmap so you can predict which combinations silently skip steps.

Legend:

• ✓ runs in normal circumstances
• ✗ skipped because the method returns early
• — not applicable for shapes (source is ShapeType)

#Shape layers (source ∈ ShapeType)

Executed via drawShape:

1. blendMode, rotation, opacity, blur
2. shadow (heart/star ⇒ shape shadow helper · otherwise rectangular applyShadow)
3. boxBackground
4. Optional borderRadius clip (rectangle path, not clipPath)
5. filters ONCE (no filterIntensity scaling, filterOrder ignored) → applyContextImageFilters over width × height
6. drawShape fill
7. stroke via applyShapeStroke following vector geometry

Unsupported on shapes: mask, distortion, meshWarp, clipPath, effects, fit/align (no raster sampling).

#Bitmap layers (source path / Buffer)

Inside drawImageBitmap:

Branching:

##A. filters && filterOrder === 'pre'

1. Paint cropped bitmap into temp canvas (dw × dh).
2. Apply filters (with filterIntensity scaling).
3. drawImage temp onto main canvas inside clip.
4. RETURN → ✗ distortion, ✗ meshWarp, ✗ mask composite path for main branch, ✗ filterOrder: 'post' filters, ✗ effects, ✗ stroke.

##B. distortion.type === 'perspective' with 4 points

Runs applyPerspectiveDistortion → RETURN → same ✗ list as A for downstream stages.

##C. distortion.type bulge / pinch

Runs applyBulgeDistortion → RETURN → same ✗ list.

##D. meshWarp.controlPoints present

Runs applyMeshWarp → RETURN → same ✗ list.

##E. Default raster path

1. mask ? applyImageMask : drawImage (respecting sx,sy,sw,sh crop).
2. Reset filter / globalAlpha · restore clip stack frame.

Still outside early returns:

6. filters && filterOrder === 'post' → snapshots box ImageData, filters (**with **filterIntensity****), clears box, redraws — ✓
7. effects → vignette / flare direct · chromatic aberration / grain via buffers — ✓
8. applyStroke on box — ✓

Final restore pops outer save from blendMode.

#Cheat sheet table

#Grouped composite

See Grouped layers: ordering mixes groupTransform shadows/clips, optional pre-filter early exit, transform stack, post-filter estimation rectangle, effects, then stroke on groupBox.