*/
#include "pipe/p_state.h"
+#include "util/u_format.h"
#include "gallivm/lp_bld_type.h"
#include "gallivm/lp_bld_const.h"
+#include "gallivm/lp_bld_arit.h"
+#include "gallivm/lp_bld_conv.h"
#include "gallivm/lp_bld_logic.h"
#include "gallivm/lp_bld_flow.h"
#include "gallivm/lp_bld_debug.h"
lp_build_alpha_test(struct gallivm_state *gallivm,
unsigned func,
struct lp_type type,
+ const struct util_format_description *cbuf_format_desc,
struct lp_build_mask_context *mask,
LLVMValueRef alpha,
LLVMValueRef ref,
lp_build_context_init(&bld, gallivm, type);
+ /*
+ * Alpha testing needs to be done in the color buffer precision.
+ *
+ * TODO: Ideally, instead of duplicating the color conversion code, we would do
+ * alpha testing after converting the output colors, but that's not very
+ * convenient, because it needs to be done before depth testing. Hopefully
+ * LLVM will detect and remove the duplicate expression.
+ *
+ * FIXME: This should be generalized to formats other than rgba8 variants.
+ */
+ if (type.floating &&
+ util_format_is_rgba8_variant(cbuf_format_desc)) {
+ const unsigned dst_width = 8;
+
+ alpha = lp_build_clamp(&bld, alpha, bld.zero, bld.one);
+ ref = lp_build_clamp(&bld, ref, bld.zero, bld.one);
+
+ alpha = lp_build_clamped_float_to_unsigned_norm(gallivm, type, dst_width, alpha);
+ ref = lp_build_clamped_float_to_unsigned_norm(gallivm, type, dst_width, ref);
+
+ type.floating = 0;
+ lp_build_context_init(&bld, gallivm, type);
+ }
+
test = lp_build_cmp(&bld, func, alpha, ref);
lp_build_name(test, "alpha_mask");