Support transparency

[maxammann]

I deliberately removed all support for transparency from maplibre-rs because it should be solved separately.

🤔 Expected Behavior

Objects with transparency should render correctly.

😯 Current Behavior

No support.

💁 Possible Solution

We can use OIT rendering like it is also used in caesium:

• https://developer.nvidia.com/content/transparency-or-translucency-rendering
• https://cesium.com/blog/2014/03/14/weighted-blended-order-independent-transparency/
• https://jcgt.org/published/0002/02/09/

🔦 Context

None

💻 Examples

None

[maxammann]

Related article: https://answers.unity.com/questions/1586184/why-the-opaque-is-rendered-not-in-the-order-of-fro.html