Lighting affecting the alpha value of a surface makes no sense

Use lighting only for RGB components, and take alpha directly from color
or material.  This should prevent problems caused by alpha>1.

diff --git a/source/program.cpp b/source/program.cpp
index 587a3fb0fa674c6c2a85689c4abee6a05d7bf2d2..7598bf1572adc036f7777fa8e9741c6086102689 100644 (file)
--- a/source/program.cpp
+++ b/source/program.cpp
@@ -73,20 +73,27 @@ const char *standard_fragment_src[] =
        /* XXX This is incorrect with normal mapping, since the vectors are in TBN
        space but environment map is expected to be in eye space */
        "e",   "\tvec4 reflection = textureCube(environment, n_normal*(dot(n_normal, v_eye_dir)*2.0)-v_eye_dir);\n",
-        0,    "\tgl_FragColor = ",
-       "!t!l!m", "vec4(1.0, 1.0, 1.0, 1.0)",
-       "t",     "texture2D(texture, v_texcoord)",
+       "t",   "\tvec4 tex_sample = texture2D(texture, v_texcoord);\n",
+        0,    "\tgl_FragColor.rgb = ",
+       "!t!l!m", "vec3(1.0)",
+       "t",     "tex_sample.rgb",
        "l|mt",  "*",
-       "!lm",   "v_color",
+       "!lm",   "v_color.rgb",
        "l",     "((l_diffuse",
-       "lm",    "*gl_FrontLightProduct[0].diffuse",
+       "lm",    "*gl_FrontLightProduct[0].diffuse.rgb",
        "p",     "+l_specular",
-       "pm",    "*gl_FrontLightProduct[0].specular",
+       "pm",    "*gl_FrontLightProduct[0].specular.rgb",
        "l",     ")",
        "s",     "*l_shadow",
-       "lm",    "+gl_FrontLightModelProduct.sceneColor",
+       "lm",    "+gl_FrontLightModelProduct.sceneColor.rgb",
        "l",     ")",
-       "e",     "+reflection*reflectivity",
+       "e",     "+reflection.rgb*reflectivity",
+        0,      ";\n",
+        0,    "\tgl_FragColor.a = ",
+       "!m",    "1.0",
+       "!lm",   "v_color.a",
+       "lm",    "gl_FrontMaterial.diffuse.a",
+       "t",     "*tex_sample.a",
         0,      ";\n",
         0,    "}\n",
        0, 0