[PATCH 1/1] wined3d: Handle a NULL "push_constants" buffer in glsl_fragment_pipe_alpha_test_func().

[Henri Verbeet]

From: Henri Verbeet

If WINED3D_RS_ALPHAREF was never set, the corresponding "push_constants"
buffer may not exist either. We don't call
glsl_fragment_pipe_alpha_test_func() when using core contexts, which is
the reason it works there. This fixes a regression introduced by commit
20fb590cfbbcc54f13cd0e2d08da4742ecdef760. Found by running the regression tests.
---
 dlls/wined3d/glsl_shader.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c
index df60415f062..000bf0d3995 100644
--- a/dlls/wined3d/glsl_shader.c
+++ b/dlls/wined3d/glsl_shader.c
@@ -12155,14 +12155,19 @@ static void glsl_fragment_pipe_tex_transform(struct wined3d_context *context,
 static void glsl_fragment_pipe_alpha_test_func(struct wined3d_context_gl *context_gl,
         const struct wined3d_state *state)
 {
-    const struct wined3d_ffp_ps_constants *constants = wined3d_buffer_load_sysmem(
-            context_gl->c.device->push_constants[WINED3D_PUSH_CONSTANTS_PS_FFP], &context_gl->c);
     const struct wined3d_gl_info *gl_info = context_gl->gl_info;
-    GLint func = wined3d_gl_compare_func(state->render_states[WINED3D_RS_ALPHAFUNC]);
+    const struct wined3d_ffp_ps_constants *constants;
+    struct wined3d_buffer *buffer;
+    GLfloat ref;
+    GLint func;

-    if (func)
+    if ((func = wined3d_gl_compare_func(state->render_states[WINED3D_RS_ALPHAFUNC])))
     {
-        gl_info->gl_ops.gl.p_glAlphaFunc(func, constants->alpha_test_ref);
+        if ((buffer = context_gl->c.device->push_constants[WINED3D_PUSH_CONSTANTS_PS_FFP]))
+            ref = (constants = wined3d_buffer_load_sysmem(buffer, &context_gl->c))->alpha_test_ref;
+        else
+            ref = 0.0f;
+        gl_info->gl_ops.gl.p_glAlphaFunc(func, ref);
         checkGLcall("glAlphaFunc");
     }
 }