Sokol shadows support

[ivan-ushakov]

No description provided.

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[ivan-ushakov]

Also tile map shader for GeforceFX (https://github.com/KD-lab-Open-Source/Perimeter/blob/cmake/Source/Render/shader/GeforceFX/tile_map_scene.psh#L54) contains commented out PCF:

dcl t0.xyzw
dcl t1.xyzw
dcl t2.xyzw
dcl t3.xyzw
dcl t4.xy
dcl t5.xy

dcl_2d s0
dcl_2d s1
dcl_2d s2
dcl_2d s4
dcl_2d s5

texld_pp  r0, t0, s0
texld_pp  r1, t1, s0
add_pp r0.rgb,r0,r1
texld_pp  r1, t2, s0
add_pp r0.rgb,r0,r1
texld_pp  r1, t3, s0

I think it was commented out because of performance but we could use it to get smooth shadows (https://learnopengl.com/Advanced-Lighting/Shadows/Shadow-Mapping).

[ivan-ushakov]

Due to complexity of adding new pipeline types (and bit shifting) I decided to search pipeline by combination of parameters from context. I keep all pipelines in vector and since we don't expect to have a lot of pipelines, search should not be a problem.

[ivan-ushakov]

wsgl does not support sampler2DShadow but in Sokol examples they use Open GL ES for this:

if (FIPS_EMSCRIPTEN)
    if (FIPS_EMSCRIPTEN_USE_WEBGPU)
        set(sokol_backend SOKOL_WGPU)
        set(slang "wgsl")
    else()
        set(sokol_backend SOKOL_GLES3)
        set(slang "glsl300es")
    endif()

[IonAgorria]

Interesting, is fine since we dont use wgpu but good to remember in future in case is needed back