1 files changed, 132 insertions, 0 deletions
diff --git a/intern/cycles/util/util_cache.h b/intern/cycles/util/util_cache.h
new file mode 100644
index 00000000000..25b1f2e7a51
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+++ b/intern/cycles/util/util_cache.h
@@ -0,0 +1,132 @@
+/*
+ * Copyright 2011, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __UTIL_CACHE_H__
+#define __UTIL_CACHE_H__
+
+/* Disk Cache based on Hashing
+ *
+ * To be used to cache expensive computations. The hash key is created from an
+ * arbitrary number of bytes, by hashing the bytes using MD5, which then gives
+ * the file name containing the data. This data then is read from the file
+ * again into the appropriate data structures.
+ *
+ * This way we do not need to accurately track changes, compare dates and
+ * invalidate cache entries, at the cost of exta computation. If everything
+ * is stored in a global cache, computations can perhaps even be shared between
+ * different scenes where it may be hard to detect duplicate work.
+ */
+
+#include "util_string.h"
+#include "util_vector.h"
+
+CCL_NAMESPACE_BEGIN
+
+class CacheBuffer {
+public:
+	const void *data;
+	size_t size;
+
+	CacheBuffer(const void *data_, size_t size_)
+	{ data = data_; size = size_; }
+};
+
+class CacheData {
+public:
+	vector<CacheBuffer> buffers;
+	string name;
+	FILE *f;
+
+	CacheData(const string& name = "");
+	~CacheData();
+
+	template<typename T> void add(const vector<T>& data)
+	{
+		CacheBuffer buffer(&data[0], data.size()*sizeof(T));
+		buffers.push_back(buffer);
+	}
+
+	template<typename T> void add(const array<T>& data)
+	{
+		CacheBuffer buffer(&data[0], data.size()*sizeof(T));
+		buffers.push_back(buffer);
+	}
+
+	void add(void *data, size_t size)
+	{
+		CacheBuffer buffer(data, size);
+		buffers.push_back(buffer);
+	}
+
+	void add(int& data)
+	{
+		CacheBuffer buffer(&data, sizeof(int));
+		buffers.push_back(buffer);
+	}
+
+	void add(size_t& data)
+	{
+		CacheBuffer buffer(&data, sizeof(size_t));
+		buffers.push_back(buffer);
+	}
+
+	template<typename T> void read(array<T>& data)
+	{
+		size_t size;
+
+		if(!fread(&size, sizeof(size), 1, f)) {
+			fprintf(stderr, "Failed to read vector size from cache.\n");
+			return;
+		}
+
+		data.resize(size/sizeof(T));
+
+		if(!fread(&data[0], size, 1, f)) {
+			fprintf(stderr, "Failed to read vector data from cache (%ld).\n", size);
+			return;
+		}
+	}
+
+	void read(int& data)
+	{
+		if(!fread(&data, sizeof(data), 1, f))
+			fprintf(stderr, "Failed to read int from cache.\n");
+	}
+
+	void read(size_t& data)
+	{
+		if(!fread(&data, sizeof(data), 1, f))
+			fprintf(stderr, "Failed to read size_t from cache.\n");
+	}
+};
+
+class Cache {
+public:
+	static Cache global;
+
+	void insert(const CacheData& key, const CacheData& value);
+	bool lookup(const CacheData& key, CacheData& value);
+
+protected:
+	string data_filename(const CacheData& key);
+};
+
+CCL_NAMESPACE_END
+
+#endif /* __UTIL_CACHE_H__ */
+