zink: set PIPE_CAP_VIEWPORT_TRANSFORM_LOWERED and remove POS special casing

this cap creates a different varying output which remains constant to be
emitted by xfb, allowing us to drop the special-casing code in ntv

Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5163>

diff --git a/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c b/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c
index 10ff16eaff2e726e362feffe72ffc98373e7b5c0..47194f655c7d03406a5c17d63a34934e97450794 100644 (file)
--- a/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c
+++ b/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c
@@ -949,22 +949,6 @@ emit_so_outputs(struct ntv_context *ctx,
       if (glsl_type_is_scalar(out_type) || (type == output_type && glsl_get_length(out_type) == so_output.num_components))
          result = src;
       else {
-         if (ctx->stage == MESA_SHADER_VERTEX && so_output.register_index == VARYING_SLOT_POS) {
-            /* gl_Position was modified by nir_lower_clip_halfz, so we need to reverse that for streamout here:
-             * 
-             * opengl gl_Position.z = (vulkan gl_Position.z * 2.0) - vulkan gl_Position.w
-             *
-             * to do this, we extract the z and w components, perform the multiply and subtract ops, then reinsert
-             */
-            uint32_t z_component[] = {2};
-            uint32_t w_component[] = {3};
-            SpvId ftype = spirv_builder_type_float(&ctx->builder, 32);
-            SpvId z = spirv_builder_emit_composite_extract(&ctx->builder, ftype, src, z_component, 1);
-            SpvId w = spirv_builder_emit_composite_extract(&ctx->builder, ftype, src, w_component, 1);
-            SpvId new_z = emit_binop(ctx, SpvOpFMul, ftype, z, spirv_builder_const_float(&ctx->builder, 32, 2.0));
-            new_z = emit_binop(ctx, SpvOpFSub, ftype, new_z, w);
-            src = spirv_builder_emit_vector_insert(&ctx->builder, type, src, new_z, 2);
-         }
          /* OpCompositeExtract can only extract scalars for our use here */
          if (so_output.num_components == 1) {
             result = spirv_builder_emit_composite_extract(&ctx->builder, type, src, components, so_output.num_components);

diff --git a/src/gallium/drivers/zink/zink_screen.c b/src/gallium/drivers/zink/zink_screen.c
index 2510715454f3d04413e193fb6718ce238f222f0f..ee5ff5041031cce97c471cd7009efc4e8430961f 100644 (file)
--- a/src/gallium/drivers/zink/zink_screen.c
+++ b/src/gallium/drivers/zink/zink_screen.c
@@ -305,6 +305,9 @@ zink_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_TGSI_FS_FACE_IS_INTEGER_SYSVAL:
       return 1;
 
+   case PIPE_CAP_VIEWPORT_TRANSFORM_LOWERED:
+      return 1;
+
    case PIPE_CAP_FLATSHADE:
    case PIPE_CAP_ALPHA_TEST:
    case PIPE_CAP_CLIP_PLANES: