Skia METAL bitmap colours appear incorrect

[AlexHarker]

Describe the bug
All bitmap drawing for me with Skia/METAL on Mac OS Ventura - 2.9 GHz Quad-Core Intel Core i7 - appears to be mapping the pixels or colours incorrectly. Black is appearing as transparent, and white a yellow, suggesting that the expected representation order of colour components is different somewhere in the system to expected. The mapping is consistent, but single channel colours do not appear to be simply transposed.

To Reproduce
Compile IGraphicsTest with Skia and METAL on Mac - view image/SVG/layer controls

Expected behaviour
Colours should draw correctly.

Screenshots

This final example shows a layer onto which four coloured circles with simple colours are drawn (r/g/b are full alpha and full on the channel noted only when drawn).

IMPORTANT DETAILS

• What plug-in format does it relate to - ALL
• What platform does it relate to - macOS
• What IGRAPHICS_BACKEND does it relate to, IGRAPHICS_SKIA with METAL

[olilarkin]

Woah, not seen that before. We are now quite behind with our skia version but also could be a macOS change causing it.

[AlexHarker]

Be good to know if it is something specific to my computer or not.

[olilarkin]

I will have a go tomorrow

[olilarkin]

I tried on intel mac with Sonoma with an AMD Radeon Pro 5500 XT 8 GB and the colours are ok here. Pretty sure I also tried it with metal when i had ventura installed on this machine