From eaef138dce6921250a4ea3ac3ccca7387098f0fc Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Wed, 7 Aug 2024 20:25:24 -0500
Subject: [PATCH] wined3d: Use the FFP HLSL pipeline for pretransformed draws
 as well.

---
 dlls/wined3d/context.c     |  2 +-
 dlls/wined3d/glsl_shader.c |  4 ++--
 dlls/wined3d/shader.c      | 20 +++++++++++++++++++-
 dlls/wined3d/stateblock.c  |  6 +++++-
 4 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/dlls/wined3d/context.c b/dlls/wined3d/context.c
index 1a6ad5dc79a..c05c833f4b3 100644
--- a/dlls/wined3d/context.c
+++ b/dlls/wined3d/context.c
@@ -161,8 +161,8 @@ void wined3d_stream_info_from_declaration(struct wined3d_stream_info *stream_inf
         const struct wined3d_state *state, const struct wined3d_d3d_info *d3d_info)
 {
     /* We need to deal with frequency data! */
+    BOOL use_vshader = use_vs(state) || (d3d_info->ffp_hlsl && state->shader[WINED3D_SHADER_TYPE_VERTEX]);
     struct wined3d_vertex_declaration *declaration = state->vertex_declaration;
-    BOOL use_vshader = use_vs(state);
     unsigned int i;
 
     stream_info->use_map = 0;
diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c
index 785050e7631..61b53da540a 100644
--- a/dlls/wined3d/glsl_shader.c
+++ b/dlls/wined3d/glsl_shader.c
@@ -10425,10 +10425,10 @@ static void set_glsl_shader_program(const struct wined3d_context_gl *context_gl,
         vs_id = ctx_data->glsl_program->vs.id;
         vs_list = &ctx_data->glsl_program->vs.shader_entry;
 
-        if (use_vs(state))
+        if (use_vs(state) || d3d_info->ffp_hlsl)
             vshader = state->shader[WINED3D_SHADER_TYPE_VERTEX];
     }
-    else if (use_vs(state))
+    else if (use_vs(state) || d3d_info->ffp_hlsl)
     {
         struct vs_compile_args vs_compile_args;
 
diff --git a/dlls/wined3d/shader.c b/dlls/wined3d/shader.c
index 2a67f3944bd..7c18c96dbf6 100644
--- a/dlls/wined3d/shader.c
+++ b/dlls/wined3d/shader.c
@@ -2701,9 +2701,27 @@ void find_vs_compile_args(const struct wined3d_state *state, const struct wined3
                 && state->transforms[WINED3D_TS_PROJECTION]._24 == 0.0f
                 && state->transforms[WINED3D_TS_PROJECTION]._34 == 0.0f
                 && state->transforms[WINED3D_TS_PROJECTION]._44 == 1.0f)
-            args->fog_src = VS_FOG_Z;
+        {
+            /* Fog source is vertex output Z.
+             *
+             * However, if drawing RHW (which means we are using an HLSL
+             * replacement shader, since we got here), and depth testing is
+             * disabled, primitives are not supposed to be clipped by the
+             * viewport. We handle this in the vertex shader by essentially
+             * flushing output Z to zero.
+             *
+             * Fog needs to still read from the original Z, however. In this
+             * case we read from oFog, which contains the original Z. */
+
+            if (state->vertex_declaration->position_transformed)
+                args->fog_src = VS_FOG_COORD;
+            else
+                args->fog_src = VS_FOG_Z;
+        }
         else
+        {
             args->fog_src = VS_FOG_W;
+        }
     }
     else
     {
diff --git a/dlls/wined3d/stateblock.c b/dlls/wined3d/stateblock.c
index 8d2bfcf8f8a..d24b356dc1f 100644
--- a/dlls/wined3d/stateblock.c
+++ b/dlls/wined3d/stateblock.c
@@ -1575,6 +1575,9 @@ void CDECL wined3d_stateblock_set_vertex_declaration(struct wined3d_stateblock *
                     || declaration->normal != prev->normal || declaration->point_size != prev->point_size)
                 stateblock->changed.ffp_vs_settings = 1;
         }
+
+        if (declaration->position_transformed != prev->position_transformed)
+            stateblock->changed.ffp_vs_settings = 1;
     }
     else
     {
@@ -3814,7 +3817,8 @@ void CDECL wined3d_device_apply_stateblock(struct wined3d_device *device,
      * FFP pipeline cares about. The rest should eventually be removed from
      * those structs and left only in vs_compile_args / ps_compile_args. */
 
-    if (changed->ffp_vs_settings && !state->vs)
+    if (changed->ffp_vs_settings
+            && (!state->vs || !state->vertex_declaration || state->vertex_declaration->position_transformed))
     {
         if (device->adapter->d3d_info.ffp_hlsl)
         {