WIP of assimp integration.

Engine/lib/assimp/code/MemoryIOWrapper.h

@@ -0,0 +1,197 @@
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2016, assimp team
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the
+following conditions are met:
+
+* Redistributions of source code must retain the above
+  copyright notice, this list of conditions and the
+  following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+  copyright notice, this list of conditions and the
+  following disclaimer in the documentation and/or other
+  materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+  contributors may be used to endorse or promote products
+  derived from this software without specific prior
+  written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----------------------------------------------------------------------
+*/
+
+/** @file MemoryIOWrapper.h
+ *  Handy IOStream/IOSystem implemetation to read directly from a memory buffer */
+#ifndef AI_MEMORYIOSTREAM_H_INC
+#define AI_MEMORYIOSTREAM_H_INC
+
+#include <assimp/IOStream.hpp>
+#include <assimp/IOSystem.hpp>
+#include <assimp/ai_assert.h>
+#include <stdint.h>
+
+namespace Assimp    {
+#define AI_MEMORYIO_MAGIC_FILENAME "$$$___magic___$$$"
+#define AI_MEMORYIO_MAGIC_FILENAME_LENGTH 17
+
+// ----------------------------------------------------------------------------------
+/** Implementation of IOStream to read directly from a memory buffer */
+// ----------------------------------------------------------------------------------
+class MemoryIOStream : public IOStream
+{
+    //friend class MemoryIOSystem;
+public:
+    MemoryIOStream (const uint8_t* buff, size_t len, bool own = false)
+        : buffer (buff)
+        , length(len)
+        , pos((size_t)0)
+        , own(own)
+    {
+    }
+
+public:
+
+    ~MemoryIOStream ()  {
+        if(own) {
+            delete[] buffer;
+        }
+    }
+
+    // -------------------------------------------------------------------
+    // Read from stream
+    size_t Read(void* pvBuffer, size_t pSize, size_t pCount)    {
+        const size_t cnt = std::min(pCount,(length-pos)/pSize),ofs = pSize*cnt;
+
+        memcpy(pvBuffer,buffer+pos,ofs);
+        pos += ofs;
+
+        return cnt;
+    }
+
+    // -------------------------------------------------------------------
+    // Write to stream
+    size_t Write(const void* /*pvBuffer*/, size_t /*pSize*/,size_t /*pCount*/)  {
+        ai_assert(false); // won't be needed
+        return 0;
+    }
+
+    // -------------------------------------------------------------------
+    // Seek specific position
+    aiReturn Seek(size_t pOffset, aiOrigin pOrigin) {
+        if (aiOrigin_SET == pOrigin) {
+            if (pOffset >= length) {
+                return AI_FAILURE;
+            }
+            pos = pOffset;
+        }
+        else if (aiOrigin_END == pOrigin) {
+            if (pOffset >= length) {
+                return AI_FAILURE;
+            }
+            pos = length-pOffset;
+        }
+        else {
+            if (pOffset+pos >= length) {
+                return AI_FAILURE;
+            }
+            pos += pOffset;
+        }
+        return AI_SUCCESS;
+    }
+
+    // -------------------------------------------------------------------
+    // Get current seek position
+    size_t Tell() const {
+        return pos;
+    }
+
+    // -------------------------------------------------------------------
+    // Get size of file
+    size_t FileSize() const {
+        return length;
+    }
+
+    // -------------------------------------------------------------------
+    // Flush file contents
+    void Flush() {
+        ai_assert(false); // won't be needed
+    }
+
+private:
+    const uint8_t* buffer;
+    size_t length,pos;
+    bool own;
+};
+
+// ---------------------------------------------------------------------------
+/** Dummy IO system to read from a memory buffer */
+class MemoryIOSystem : public IOSystem
+{
+public:
+    /** Constructor. */
+    MemoryIOSystem (const uint8_t* buff, size_t len)
+        : buffer (buff), length(len) {
+    }
+
+    /** Destructor. */
+    ~MemoryIOSystem() {
+    }
+
+    // -------------------------------------------------------------------
+    /** Tests for the existence of a file at the given path. */
+    bool Exists( const char* pFile) const {
+        return !strncmp(pFile,AI_MEMORYIO_MAGIC_FILENAME,AI_MEMORYIO_MAGIC_FILENAME_LENGTH);
+    }
+
+    // -------------------------------------------------------------------
+    /** Returns the directory separator. */
+    char getOsSeparator() const {
+        return '/'; // why not? it doesn't care
+    }
+
+    // -------------------------------------------------------------------
+    /** Open a new file with a given path. */
+    IOStream* Open( const char* pFile, const char* /*pMode*/ = "rb") {
+        if (strncmp(pFile,AI_MEMORYIO_MAGIC_FILENAME,AI_MEMORYIO_MAGIC_FILENAME_LENGTH)) {
+            return NULL;
+        }
+        return new MemoryIOStream(buffer,length);
+    }
+
+    // -------------------------------------------------------------------
+    /** Closes the given file and releases all resources associated with it. */
+    void Close( IOStream* pFile) {
+    	delete pFile;
+    }
+
+    // -------------------------------------------------------------------
+    /** Compare two paths */
+    bool ComparePaths (const char* /*one*/, const char* /*second*/) const {
+        return false;
+    }
+
+private:
+    const uint8_t* buffer;
+    size_t length;
+};
+} // end namespace Assimp
+
+#endif