Metal: GLSL Compatibility - Hosting default uniform values.

There are a number of shaders, most notably grid_frag.glsl, which rely on default assignments to uniform values within shaders. This is not currently supported by the shader uniform push model implemented for the Metal backend, wherein uniform updates are pushed as a singular block of data. Any default assignment would become over-written.

As such, adding assignments of these default values in the high-level, to ensure the correct value is written for all APIs. This likely impacts Vulkan push-constants as well.

Authored by Apple: Michael Parkin-White

Ref T96261

Reviewed By: fclem

Maniphest Tasks: T96261

Differential Revision: https://developer.blender.org/D14555

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/draw/engines/eevee/eevee_materials.c b/source/blender/draw/engines/eevee/eevee_materials.c
index c46e5dd75d6..a81d3e56673 100644
--- a/source/blender/draw/engines/eevee/eevee_materials.c
+++ b/source/blender/draw/engines/eevee/eevee_materials.c
@@ -113,6 +113,9 @@ void EEVEE_material_bind_resources(DRWShadingGroup *shgrp,
     DRW_shgroup_uniform_texture_ref(shgrp, "probePlanars", &vedata->txl->planar_pool);
     DRW_shgroup_uniform_int_copy(shgrp, "outputSsrId", ssr_id ? *ssr_id : 0);
   }
+  else {
+    DRW_shgroup_uniform_int_copy(shgrp, "outputSsrId", 1);
+  }
   if (use_refract) {
     DRW_shgroup_uniform_float_copy(
         shgrp, "refractionDepth", (refract_depth) ? *refract_depth : 0.0);