Step 6. Compare the BBox-Warp + Landmark Gaps pipeline

Time: 5 minutes.

Why a second pipeline

The Polar pipeline you ran in chapter 5 is fast and reads well on butterfly wings. The second starred recommended pipeline, BBox-Warp then Landmark Gaps, trades raw speed for fine-grain control. It is the right choice when:

• The source photo and the model differ in proportions (a stockier Monarch with a slim Blue Morpho photo, for instance).
• You need precise pattern alignment on small features (eye spots, veins).
• You plan to do touch-ups by hand after the bake.

This chapter runs the BBox pipeline, lets you compare the two bakes side by side, and helps you decide which to ship.

Undo back to a clean Monarch

Before running BBox you want a fresh start. Press Cmd+Z (macOS) or Ctrl+Z (Windows/Linux) until the canvas shows the original Monarch albedo (no Blue Morpho tint). The undo history will tell you when you have rewound past the Polar bake.

Alternatively, set the butterfly placement's texture_path back to the original by clicking the Channel Box value and editing it to _3ds/texture.bmp.

Verify the canvas shows the original Monarch orange before you continue.

Run BBox-Warp + Landmark Gaps

With the model still selected, choose Mesh > Transfer Texture > BBox-Warp then Landmark Gaps + Bake + Normal Map.

The Designer runs four stages:

1. BBox-Warp: maps the source photo into the model's UV bounding box. This is faster than TPS but less accurate near features.
2. Landmark Gaps: identifies where the BBox warp's accuracy degrades (typically the wing tips and the body-wing junction) and re-runs a thin-plate spline locally over those regions using your six landmark pairs.
3. Bake: writes the combined result to textures/butterfly_albedo.png.
4. Normal map: derives the same high-frequency normal map and writes it to textures/butterfly_normal.png.

The HUD shows four progress bars this time, one per stage. End-to-end runtime is about 8 to 10 seconds.

Compare the two bakes

The Designer keeps both bakes in its undo history. To do an A/B:

1. Press Cmd+Z (macOS) or Ctrl+Z (Windows/Linux). The canvas reverts to the Polar bake from chapter 5.
2. Press Cmd+Shift+Z or Ctrl+Shift+Z (or use Edit > Redo) to come back to the BBox bake.

Toggle back and forth a few times. Pay attention to:

• Wing tip iridescence: Polar usually wins (smoother gradient).
• Vein alignment: BBox+Landmark usually wins (sharper edges).
• Body color: both should preserve the original Monarch orange.

Which wins for your project depends on what kind of app you are building. For the official Elysium logo banner the rest of this tutorial assumes we ship Polar (chapter 5's result). If you prefer BBox+Landmark, simply stay on it; chapters 7 and 8 work the same either way.

Pick a winner

Press Cmd+Z / Ctrl+Z until the canvas shows the bake you want to ship. The Channel Box's texture_path and the Assets tab's texture files will reflect your choice.

A note on the other 7 transfer methods

The Mesh > Transfer Texture submenu also lists POLAR, REGIONS, FLOW, TPS, BBOX_WARP, SWEEP, and LANDMARK as standalone methods without the bake-and-normal-map steps. They are mainly useful when:

• You want to compose a custom pipeline (e.g. TPS into a separate layer, hand-tune, then bake yourself).
• You are debugging a recommended pipeline that did something unexpected on your specific model.
• You are porting an existing wing texture from another tool.

The Rendering > Texture transfer pipelines reference page explains every method's algorithm and trade-offs.

Checkpoint

You should see:

• The canvas showing your chosen bake (Polar or BBox+Landmark).
• The same two texture files in the Assets tab as in chapter 5.
• A muscle memory for Cmd+Z / Cmd+Shift+Z to flip between history states.

Continue to chapter 7 >>