[instinkt900]

Problem

Tiled anchors a tile object (an object with a gid) at its bottom-left corner. A plain
rectangle or ellipse object is anchored top-left. drawObjectLayer passed the object's position
straight through as the top-left:

drawTileImage(*tileset, resolvedId, object.tile, object.position + offset, object.rotation, scale);

So every tile object drew one full height below where the editor showed it. The error scales with
the object, so small decoration looks roughly right while anything large is plainly misplaced.

Seen in TinCan: a decoration object placed at y=5712 with a drawn height of 192 should render from
y=5520, and rendered from y=5712 — 192px low, sitting well below the ground tiles it was aligned to.

Fix

Shift the draw position up by the drawn height:

FloatVec2 topLeft = object.position + offset;
topLeft.y -= static_cast<float>(sourceRect.h()) * scale.y;

Using sourceRect.h() * scale.y rather than the tile's natural height means a resized tile object
moves by the height the editor actually shows.

Tests

Renderer: draws tile objects from object layers, skipping shapes asserted the old position, so it
was pinning the bug in place — it now expects y=-8 for a 16px tile placed at y=8.

Added Renderer: a resized tile object is anchored at its scaled bottom-left to cover the scaled
case, which needed a scale field on the mock's DrawCall (the mock recorded position, pivot and
rotation but not scale).

Not covered here

Tiled also rotates a tile object about that same bottom-left anchor, while drawTileImage pivots
about the tile centre (tile_map_renderer.cpp:72-75). A rotated tile object is still misplaced
after this change. That sits in the flip-flag composition and is left for its own change.

Downstream

Any map that was authored against the old behaviour — by nudging tile objects up to compensate —
will need those objects moved back.

[coderabbitai]

Important

• 🔍 Trigger review

This repository does not receive automatic reviews because it has fewer than 10 stars.

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Advanced

Run ID: 000182a0-5cc5-44df-bf85-c900e4ffc919

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}