forge-stencil-testing

To enable stencil buffer testing in an SDL GPU project, create a depth-stencil texture with stencil bits like D24_UNORM_S8_UINT and configure the pipeline stencil states for both front and back faces. This setup enables per-pixel masking for portal and outline effects.

Rendering portal effects using the stencil buffer in SDL involves applying per-draw stencil references to selectively mask portal regions. By configuring stencil states, you can reveal alternate scenes through the stencil mask while maintaining correct depth behavior.

SDL GPU supports per-pixel masking for object outlines by configuring pipeline stencil tests. By defining a depth-stencil texture and using per-draw stencil references, you can selectively render masked overlays and outlines for your graphics objects.

Stencil states for front and back faces control how depth-stencil operations evaluate per-pixel masking independently based on polygon orientation. Configuring both ensures correct depth behavior when selectively rendering portal regions and outlines in SDL GPU.

You need a D24_UNORM_S8_UINT texture for stencil operations in SDL because it provides the dedicated 8-bit stencil buffer required for per-pixel masking. This format enables the stencil testing mechanism needed to render portals and outlines correctly.