Implement 'faceforward' builtin.
diff --git a/builtin_function.cpp b/builtin_function.cpp
index bdcf891..754a721 100644
--- a/builtin_function.cpp
+++ b/builtin_function.cpp
@@ -689,6 +689,46 @@
"))\n"
};
+static const char *builtins_110_faceforward = {
+ "((function faceforward\n"
+ " (signature float\n"
+ " (parameters\n"
+ " (declare (in) float N)\n"
+ " (declare (in) float I)\n"
+ " (declare (in) float Nref))\n"
+ " ((if (expression bool < (expression float dot (var_ref Nref) (var_ref I)) (constant float (0)))\n"
+ " ((return (var_ref N)))\n"
+ " ((return (expression float neg (var_ref N)))))))\n"
+ "\n"
+ " (signature vec2\n"
+ " (parameters\n"
+ " (declare (in) vec2 N)\n"
+ " (declare (in) vec2 I)\n"
+ " (declare (in) vec2 Nref))\n"
+ " ((if (expression bool < (expression float dot (var_ref Nref) (var_ref I)) (constant float (0)))\n"
+ " ((return (var_ref N)))\n"
+ " ((return (expression vec2 neg (var_ref N)))))))\n"
+ "\n"
+ " (signature vec3\n"
+ " (parameters\n"
+ " (declare (in) vec3 N)\n"
+ " (declare (in) vec3 I)\n"
+ " (declare (in) vec3 Nref))\n"
+ " ((if (expression bool < (expression float dot (var_ref Nref) (var_ref I)) (constant float (0)))\n"
+ " ((return (var_ref N)))\n"
+ " ((return (expression vec3 neg (var_ref N)))))))\n"
+ "\n"
+ " (signature vec4\n"
+ " (parameters\n"
+ " (declare (in) vec4 N)\n"
+ " (declare (in) vec4 I)\n"
+ " (declare (in) vec4 Nref))\n"
+ " ((if (expression bool < (expression float dot (var_ref Nref) (var_ref I)) (constant float (0)))\n"
+ " ((return (var_ref N)))\n"
+ " ((return (expression vec4 neg (var_ref N)))))))\n"
+ "))\n"
+};
+
static const char *builtins_110_floor = {
"((function floor\n"
" (signature float\n"
@@ -2215,6 +2255,7 @@
builtins_110_equal,
builtins_110_exp,
builtins_110_exp2,
+ builtins_110_faceforward,
builtins_110_floor,
builtins_110_fract,
builtins_110_greaterThan,