Welcome to mirror list, hosted at ThFree Co, Russian Federation.

git.blender.org/blender.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat (limited to 'extern/draco/draco/src/draco/core/divide.h')
-rw-r--r--extern/draco/draco/src/draco/core/divide.h42
1 files changed, 42 insertions, 0 deletions
diff --git a/extern/draco/draco/src/draco/core/divide.h b/extern/draco/draco/src/draco/core/divide.h
new file mode 100644
index 00000000000..7e3838a008c
--- /dev/null
+++ b/extern/draco/draco/src/draco/core/divide.h
@@ -0,0 +1,42 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_CORE_DIVIDE_H_
+#define DRACO_CORE_DIVIDE_H_
+// An implementation of the divide by multiply algorithm
+// https://gmplib.org/~tege/divcnst-pldi94.pdf
+// This file is based off libvpx's divide.h.
+
+#include <stdint.h>
+
+#include <climits>
+
+namespace draco {
+
+struct fastdiv_elem {
+ unsigned mult;
+ unsigned shift;
+};
+
+extern const struct fastdiv_elem vp10_fastdiv_tab[256];
+
+static inline unsigned fastdiv(unsigned x, int y) {
+ unsigned t =
+ ((uint64_t)x * vp10_fastdiv_tab[y].mult) >> (sizeof(x) * CHAR_BIT);
+ return (t + x) >> vp10_fastdiv_tab[y].shift;
+}
+
+} // namespace draco
+
+#endif // DRACO_CORE_DIVIDE_H_