Contour lines are applied on transparent pixels

ℹ️ Funded by an industrial customer.

Summary

If we enable contour lines on a map with some transparent pixels (such as masked areas), the contour lines are still visible.

Steps to reproduce

1. Modify the mask_layer example to add an elevation layer
2. Enable contour lines on the map

Expected behaviour:

Contour lines should not be visible on transparent map pixels.

Actual behaviour:

Contour lines are applied on transparent map pixels.

Informations

• Giro3D version: 0.29
• Browser (Firefox, Chrome, Opera, Safari...) and version: N/A
• OS (Linux, MacOS, Windows...) N/A

Screenshots