nuclear@0: /*
nuclear@0: ---------------------------------------------------------------------------
nuclear@0: Open Asset Import Library (assimp)
nuclear@0: ---------------------------------------------------------------------------
nuclear@0: 
nuclear@0: Copyright (c) 2006-2012, assimp team
nuclear@0: 
nuclear@0: All rights reserved.
nuclear@0: 
nuclear@0: Redistribution and use of this software in source and binary forms, 
nuclear@0: with or without modification, are permitted provided that the following 
nuclear@0: conditions are met:
nuclear@0: 
nuclear@0: * Redistributions of source code must retain the above
nuclear@0:   copyright notice, this list of conditions and the
nuclear@0:   following disclaimer.
nuclear@0: 
nuclear@0: * Redistributions in binary form must reproduce the above
nuclear@0:   copyright notice, this list of conditions and the
nuclear@0:   following disclaimer in the documentation and/or other
nuclear@0:   materials provided with the distribution.
nuclear@0: 
nuclear@0: * Neither the name of the assimp team, nor the names of its
nuclear@0:   contributors may be used to endorse or promote products
nuclear@0:   derived from this software without specific prior
nuclear@0:   written permission of the assimp team.
nuclear@0: 
nuclear@0: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
nuclear@0: "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
nuclear@0: LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
nuclear@0: A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
nuclear@0: OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
nuclear@0: SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
nuclear@0: LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
nuclear@0: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
nuclear@0: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
nuclear@0: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
nuclear@0: OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
nuclear@0: ---------------------------------------------------------------------------
nuclear@0: */
nuclear@0: 
nuclear@0: /** @file Implementation of the Terragen importer class */
nuclear@0: 
nuclear@0: #include "AssimpPCH.h"
nuclear@0: 
nuclear@0: #ifndef ASSIMP_BUILD_NO_TERRAGEN_IMPORTER
nuclear@0: #include "TerragenLoader.h"
nuclear@0: 
nuclear@0: using namespace Assimp;
nuclear@0: 
nuclear@0: static const aiImporterDesc desc = {
nuclear@0: 	"Terragen Heightmap Importer",
nuclear@0: 	"",
nuclear@0: 	"",
nuclear@0: 	"http://www.planetside.co.uk/",
nuclear@0: 	aiImporterFlags_SupportBinaryFlavour,
nuclear@0: 	0,
nuclear@0: 	0,
nuclear@0: 	0,
nuclear@0: 	0,
nuclear@0: 	"ter" 
nuclear@0: };
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Constructor to be privately used by Importer
nuclear@0: TerragenImporter::TerragenImporter()
nuclear@0: : configComputeUVs (false)
nuclear@0: {}
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Destructor, private as well 
nuclear@0: TerragenImporter::~TerragenImporter()
nuclear@0: {}
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Returns whether the class can handle the format of the given file. 
nuclear@0: bool TerragenImporter::CanRead( const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const
nuclear@0: {
nuclear@0: 	// check file extension 
nuclear@0: 	std::string extension = GetExtension(pFile);
nuclear@0: 	
nuclear@0: 	if( extension == "ter")
nuclear@0: 		return true;
nuclear@0: 
nuclear@0: 	if(  !extension.length() || checkSig)	{
nuclear@0: 		/*  If CanRead() is called in order to check whether we
nuclear@0: 		 *  support a specific file extension in general pIOHandler
nuclear@0: 		 *  might be NULL and it's our duty to return true here.
nuclear@0: 		 */
nuclear@0: 		if (!pIOHandler)return true;
nuclear@0: 		const char* tokens[] = {"terragen"};
nuclear@0: 		return SearchFileHeaderForToken(pIOHandler,pFile,tokens,1);
nuclear@0: 	}
nuclear@0: 	return false;
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Build a string of all file extensions supported
nuclear@0: const aiImporterDesc* TerragenImporter::GetInfo () const
nuclear@0: {
nuclear@0: 	return &desc;
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Setup import properties
nuclear@0: void TerragenImporter::SetupProperties(const Importer* pImp)
nuclear@0: {
nuclear@0: 	// AI_CONFIG_IMPORT_TER_MAKE_UVS
nuclear@0: 	configComputeUVs = ( 0 != pImp->GetPropertyInteger(AI_CONFIG_IMPORT_TER_MAKE_UVS,0) );
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Imports the given file into the given scene structure. 
nuclear@0: void TerragenImporter::InternReadFile( const std::string& pFile, 
nuclear@0: 	aiScene* pScene, IOSystem* pIOHandler)
nuclear@0: {
nuclear@0: 	IOStream* file = pIOHandler->Open( pFile, "rb");
nuclear@0: 
nuclear@0: 	// Check whether we can read from the file
nuclear@0: 	if( file == NULL)
nuclear@0: 		throw DeadlyImportError( "Failed to open TERRAGEN TERRAIN file " + pFile + ".");
nuclear@0: 
nuclear@0: 	// Construct a stream reader to read all data in the correct endianess
nuclear@0: 	StreamReaderLE reader(file);
nuclear@0: 	if(reader.GetRemainingSize() < 16)
nuclear@0: 		throw DeadlyImportError( "TER: file is too small" );
nuclear@0: 
nuclear@0: 	// Check for the existence of the two magic strings 'TERRAGEN' and 'TERRAIN '
nuclear@0: 	if (::strncmp((const char*)reader.GetPtr(),AI_TERR_BASE_STRING,8))
nuclear@0: 		throw DeadlyImportError( "TER: Magic string \'TERRAGEN\' not found" );
nuclear@0: 
nuclear@0: 	if (::strncmp((const char*)reader.GetPtr()+8,AI_TERR_TERRAIN_STRING,8))
nuclear@0: 		throw DeadlyImportError( "TER: Magic string \'TERRAIN\' not found" );
nuclear@0: 
nuclear@0: 	unsigned int x = 0,y = 0,mode = 0;
nuclear@0: 	float rad  = 6370.f;
nuclear@0: 	(void)rad;
nuclear@0: 
nuclear@0: 
nuclear@0: 	aiNode* root = pScene->mRootNode = new aiNode();
nuclear@0: 	root->mName.Set("<TERRAGEN.TERRAIN>");
nuclear@0: 
nuclear@0: 	// Default scaling is 30
nuclear@0: 	root->mTransformation.a1 = root->mTransformation.b2 = root->mTransformation.c3 = 30.f;
nuclear@0: 
nuclear@0: 	// Now read all chunks until we're finished or an EOF marker is encountered
nuclear@0: 	reader.IncPtr(16);
nuclear@0: 	while (reader.GetRemainingSize() >= 4)	
nuclear@0: 	{
nuclear@0: 		const char* head = (const char*)reader.GetPtr();
nuclear@0: 		reader.IncPtr(4);
nuclear@0: 
nuclear@0: 		// EOF, break in every case
nuclear@0: 		if (!::strncmp(head,AI_TERR_EOF_STRING,4))
nuclear@0: 			break;
nuclear@0: 
nuclear@0: 		// Number of x-data points
nuclear@0: 		if (!::strncmp(head,AI_TERR_CHUNK_XPTS,4))
nuclear@0: 		{
nuclear@0: 			x = (uint16_t)reader.GetI2();
nuclear@0: 		}
nuclear@0: 		// Number of y-data points
nuclear@0: 		else if (!::strncmp(head,AI_TERR_CHUNK_YPTS,4))
nuclear@0: 		{
nuclear@0: 			y = (uint16_t)reader.GetI2();
nuclear@0: 		}
nuclear@0: 		// Squared terrains width-1. 
nuclear@0: 		else if (!::strncmp(head,AI_TERR_CHUNK_SIZE,4))
nuclear@0: 		{
nuclear@0: 			x = y = (uint16_t)reader.GetI2()+1;
nuclear@0: 		}
nuclear@0: 		// terrain scaling
nuclear@0: 		else if (!::strncmp(head,AI_TERR_CHUNK_SCAL,4))
nuclear@0: 		{
nuclear@0: 			root->mTransformation.a1 = reader.GetF4();
nuclear@0: 			root->mTransformation.b2 = reader.GetF4();
nuclear@0: 			root->mTransformation.c3 = reader.GetF4();
nuclear@0: 		}
nuclear@0: 		// mapping == 1: earth radius
nuclear@0: 		else if (!::strncmp(head,AI_TERR_CHUNK_CRAD,4))
nuclear@0: 		{
nuclear@0: 			rad = reader.GetF4();
nuclear@0: 		}
nuclear@0: 		// mapping mode
nuclear@0: 		else if (!::strncmp(head,AI_TERR_CHUNK_CRVM,4))
nuclear@0: 		{
nuclear@0: 			mode = reader.GetI1();
nuclear@0: 			if (0 != mode)
nuclear@0: 				DefaultLogger::get()->error("TER: Unsupported mapping mode, a flat terrain is returned");
nuclear@0: 		}
nuclear@0: 		// actual terrain data
nuclear@0: 		else if (!::strncmp(head,AI_TERR_CHUNK_ALTW,4))
nuclear@0: 		{
nuclear@0: 			float hscale  = (float)reader.GetI2()  / 65536;
nuclear@0: 			float bheight = (float)reader.GetI2();
nuclear@0: 
nuclear@0: 			if (!hscale)hscale = 1;
nuclear@0: 
nuclear@0: 			// Ensure we have enough data
nuclear@0: 			if (reader.GetRemainingSize() < x*y*2)
nuclear@0: 				throw DeadlyImportError("TER: ALTW chunk is too small");
nuclear@0: 
nuclear@0: 			if (x <= 1 || y <= 1)
nuclear@0: 				throw DeadlyImportError("TER: Invalid terrain size");
nuclear@0: 
nuclear@0: 			// Allocate the output mesh
nuclear@0: 			pScene->mMeshes = new aiMesh*[pScene->mNumMeshes = 1];
nuclear@0: 			aiMesh* m = pScene->mMeshes[0] = new aiMesh();
nuclear@0: 
nuclear@0: 			// We return quads
nuclear@0: 			aiFace* f = m->mFaces = new aiFace[m->mNumFaces = (x-1)*(y-1)];
nuclear@0: 			aiVector3D* pv = m->mVertices = new aiVector3D[m->mNumVertices = m->mNumFaces*4];
nuclear@0: 			
nuclear@0: 			aiVector3D *uv( NULL );
nuclear@0: 			float step_y( 0.0f ), step_x( 0.0f );
nuclear@0: 			if (configComputeUVs) {
nuclear@0: 				uv = m->mTextureCoords[0] = new aiVector3D[m->mNumVertices];
nuclear@0: 				step_y = 1.f/y;
nuclear@0: 				step_x = 1.f/x;
nuclear@0: 			}
nuclear@0: 			const int16_t* data = (const int16_t*)reader.GetPtr();
nuclear@0: 
nuclear@0: 			for (unsigned int yy = 0, t = 0; yy < y-1;++yy)	{
nuclear@0: 				for (unsigned int xx = 0; xx < x-1;++xx,++f)	{
nuclear@0: 
nuclear@0: 					// make verts
nuclear@0: 					const float fy = (float)yy, fx = (float)xx;
nuclear@0: 					register unsigned tmp,tmp2;
nuclear@0: 					*pv++ = aiVector3D(fx,fy,    (float)data[(tmp2=x*yy)    + xx] * hscale + bheight);
nuclear@0: 					*pv++ = aiVector3D(fx,fy+1,  (float)data[(tmp=x*(yy+1)) + xx] * hscale + bheight);
nuclear@0: 					*pv++ = aiVector3D(fx+1,fy+1,(float)data[tmp  + xx+1]         * hscale + bheight);
nuclear@0: 					*pv++ = aiVector3D(fx+1,fy,  (float)data[tmp2 + xx+1]         * hscale + bheight);
nuclear@0: 
nuclear@0: 					// also make texture coordinates, if necessary
nuclear@0: 					if (configComputeUVs) {
nuclear@0: 						*uv++ = aiVector3D( step_x*xx,     step_y*yy,     0.f );
nuclear@0: 						*uv++ = aiVector3D( step_x*xx,     step_y*(yy+1), 0.f );
nuclear@0: 						*uv++ = aiVector3D( step_x*(xx+1), step_y*(yy+1), 0.f );
nuclear@0: 						*uv++ = aiVector3D( step_x*(xx+1), step_y*yy,     0.f );
nuclear@0: 					}
nuclear@0: 
nuclear@0: 					// make indices
nuclear@0: 					f->mIndices = new unsigned int[f->mNumIndices = 4];
nuclear@0: 					for (unsigned int i = 0; i < 4;++i)
nuclear@0: 						f->mIndices[i] = t++;
nuclear@0: 				}
nuclear@0: 			}
nuclear@0: 
nuclear@0: 			// Add the mesh to the root node
nuclear@0: 			root->mMeshes = new unsigned int[root->mNumMeshes = 1];
nuclear@0: 			root->mMeshes[0] = 0;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		// Get to the next chunk (4 byte aligned)
nuclear@0: 		unsigned dtt;
nuclear@0: 		if ((dtt = reader.GetCurrentPos() & 0x3))
nuclear@0: 			reader.IncPtr(4-dtt);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	// Check whether we have a mesh now
nuclear@0: 	if (pScene->mNumMeshes != 1)
nuclear@0: 		throw DeadlyImportError("TER: Unable to load terrain");
nuclear@0: 
nuclear@0: 	// Set the AI_SCENE_FLAGS_TERRAIN bit
nuclear@0: 	pScene->mFlags |= AI_SCENE_FLAGS_TERRAIN;
nuclear@0: }
nuclear@0: 
nuclear@0: #endif // !! ASSIMP_BUILD_NO_TERRAGEN_IMPORTER