[PATCH v2 1/2] wined3d: Use 3 component norm for 'nrm' opcode in GLSL backend.

[Paul Gofman]

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=8848
Signed-off-by: Paul Gofman <gofmanp at gmail.com>
---
v2: no changes.

 dlls/wined3d/glsl_shader.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c
index 9d4f6057c3..6239467741 100644
--- a/dlls/wined3d/glsl_shader.c
+++ b/dlls/wined3d/glsl_shader.c
@@ -4265,11 +4265,24 @@ static void shader_glsl_nrm(const struct wined3d_shader_instruction *ins)
     mask_size = shader_glsl_get_write_mask_size(write_mask);
     shader_glsl_add_src_param(ins, &ins->src[0], write_mask, &src_param);
 
-    shader_addline(buffer, "tmp0.x = dot(%s, %s);\n",
-            src_param.param_str, src_param.param_str);
+    if (mask_size > 3)
+        shader_addline(buffer, "tmp0.x = dot(vec3(%s), vec3(%s));\n",
+                src_param.param_str, src_param.param_str);
+    else
+        shader_addline(buffer, "tmp0.x = dot(%s, %s);\n",
+                src_param.param_str, src_param.param_str);
     shader_glsl_append_dst(buffer, ins);
 
-    if (mask_size > 1)
+    if (mask_size == 4)
+    {
+        static const float max_float = FLT_MAX;
+
+        shader_addline(buffer, "tmp0.x == 0.0 ? vec4(vec3(0.0), sign(%s[3]) * ",
+                src_param.param_str);
+        shader_glsl_append_imm_vec(buffer, &max_float, 1, ins->ctx->gl_info);
+        shader_addline(buffer, ") : (%s * inversesqrt(tmp0.x)));\n", src_param.param_str);
+    }
+    else if (mask_size > 1)
     {
         shader_addline(buffer, "tmp0.x == 0.0 ? vec%u(0.0) : (%s * inversesqrt(tmp0.x)));\n",
                 mask_size, src_param.param_str);
-- 
2.21.0