// Copyright (C) 2006-2012 Luke Hoschke
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

// B3D Mesh loader
// File format designed by Mark Sibly for the Blitz3D engine and has been
// declared public domain

#include "CB3DMeshFileLoader.h"

#include "IVideoDriver.h"
#include "IFileSystem.h"
#include "os.h"

#include <algorithm>

#ifdef _DEBUG
#define _B3D_READER_DEBUG
#endif

namespace irr
{
namespace scene
{

//! Constructor
CB3DMeshFileLoader::CB3DMeshFileLoader(scene::ISceneManager *smgr) :
		AnimatedMesh(0), B3DFile(0), VerticesStart(0), NormalsInFile(false),
		HasVertexColors(false), ShowWarning(true)
{
#ifdef _DEBUG
	setDebugName("CB3DMeshFileLoader");
#endif
}

//! returns true if the file maybe is able to be loaded by this class
//! based on the file extension (e.g. ".bsp")
bool CB3DMeshFileLoader::isALoadableFileExtension(const io::path &filename) const
{
	return core::hasFileExtension(filename, "b3d");
}

//! creates/loads an animated mesh from the file.
//! \return Pointer to the created mesh. Returns 0 if loading failed.
//! If you no longer need the mesh, you should call IAnimatedMesh::drop().
//! See IReferenceCounted::drop() for more information.
IAnimatedMesh *CB3DMeshFileLoader::createMesh(io::IReadFile *file)
{
	if (!file)
		return 0;

	B3DFile = file;
	AnimatedMesh = new scene::CSkinnedMesh();
	ShowWarning = true; // If true a warning is issued if too many textures are used
	VerticesStart = 0;

	if (load()) {
		AnimatedMesh->finalize();
	} else {
		AnimatedMesh->drop();
		AnimatedMesh = 0;
	}

	return AnimatedMesh;
}

bool CB3DMeshFileLoader::load()
{
	B3dStack.clear();

	NormalsInFile = false;
	HasVertexColors = false;

	//------ Get header ------

	SB3dChunkHeader header;
	B3DFile->read(&header, sizeof(header));
#ifdef __BIG_ENDIAN__
	header.size = os::Byteswap::byteswap(header.size);
#endif

	if (strncmp(header.name, "BB3D", 4) != 0) {
		os::Printer::log("File is not a b3d file. Loading failed (No header found)", B3DFile->getFileName(), ELL_ERROR);
		return false;
	}

	// Add main chunk...
	B3dStack.push_back(SB3dChunk(header, B3DFile->getPos() - 8));

	// Get file version, but ignore it, as it's not important with b3d files...
	s32 fileVersion;
	B3DFile->read(&fileVersion, sizeof(fileVersion));
#ifdef __BIG_ENDIAN__
	fileVersion = os::Byteswap::byteswap(fileVersion);
#endif

	//------ Read main chunk ------

	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) {
		B3DFile->read(&header, sizeof(header));
#ifdef __BIG_ENDIAN__
		header.size = os::Byteswap::byteswap(header.size);
#endif
		B3dStack.push_back(SB3dChunk(header, B3DFile->getPos() - 8));

		if (strncmp(B3dStack.getLast().name, "TEXS", 4) == 0) {
			if (!readChunkTEXS())
				return false;
		} else if (strncmp(B3dStack.getLast().name, "BRUS", 4) == 0) {
			if (!readChunkBRUS())
				return false;
		} else if (strncmp(B3dStack.getLast().name, "NODE", 4) == 0) {
			if (!readChunkNODE((CSkinnedMesh::SJoint *)0))
				return false;
		} else {
			os::Printer::log("Unknown chunk found in mesh base - skipping");
			if (!B3DFile->seek(B3dStack.getLast().startposition + B3dStack.getLast().length))
				return false;
			B3dStack.erase(B3dStack.size() - 1);
		}
	}

	B3dStack.clear();

	BaseVertices.clear();
	AnimatedVertices_VertexID.clear();
	AnimatedVertices_BufferID.clear();

	Materials.clear();
	Textures.clear();

	return true;
}

bool CB3DMeshFileLoader::readChunkNODE(CSkinnedMesh::SJoint *inJoint)
{
	CSkinnedMesh::SJoint *joint = AnimatedMesh->addJoint(inJoint);
	joint->Name = readString();

#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "read ChunkNODE";
	os::Printer::log(logStr.c_str(), joint->Name.value_or("").c_str(), ELL_DEBUG);
#endif

	f32 position[3], scale[3], rotation[4];

	readFloats(position, 3);
	readFloats(scale, 3);
	readFloats(rotation, 4);

	joint->Animatedposition = core::vector3df(position[0], position[1], position[2]);
	joint->Animatedscale = core::vector3df(scale[0], scale[1], scale[2]);
	joint->Animatedrotation = core::quaternion(rotation[1], rotation[2], rotation[3], rotation[0]);

	// Build LocalMatrix:

	core::matrix4 positionMatrix;
	positionMatrix.setTranslation(joint->Animatedposition);
	core::matrix4 scaleMatrix;
	scaleMatrix.setScale(joint->Animatedscale);
	core::matrix4 rotationMatrix;
	joint->Animatedrotation.getMatrix_transposed(rotationMatrix);

	joint->LocalMatrix = positionMatrix * rotationMatrix * scaleMatrix;

	if (inJoint)
		joint->GlobalMatrix = inJoint->GlobalMatrix * joint->LocalMatrix;
	else
		joint->GlobalMatrix = joint->LocalMatrix;

	while (B3dStack.getLast().startposition + B3dStack.getLast().length > B3DFile->getPos()) // this chunk repeats
	{
		SB3dChunkHeader header;
		B3DFile->read(&header, sizeof(header));
#ifdef __BIG_ENDIAN__
		header.size = os::Byteswap::byteswap(header.size);
#endif

		B3dStack.push_back(SB3dChunk(header, B3DFile->getPos() - 8));

		if (strncmp(B3dStack.getLast().name, "NODE", 4) == 0) {
			if (!readChunkNODE(joint))
				return false;
		} else if (strncmp(B3dStack.getLast().name, "MESH", 4) == 0) {
			VerticesStart = BaseVertices.size();
			if (!readChunkMESH(joint))
				return false;
		} else if (strncmp(B3dStack.getLast().name, "BONE", 4) == 0) {
			if (!readChunkBONE(joint))
				return false;
		} else if (strncmp(B3dStack.getLast().name, "KEYS", 4) == 0) {
			if (!readChunkKEYS(joint))
				return false;
		} else if (strncmp(B3dStack.getLast().name, "ANIM", 4) == 0) {
			if (!readChunkANIM())
				return false;
		} else {
			os::Printer::log("Unknown chunk found in node chunk - skipping");
			if (!B3DFile->seek(B3dStack.getLast().startposition + B3dStack.getLast().length))
				return false;
			B3dStack.erase(B3dStack.size() - 1);
		}
	}

	B3dStack.erase(B3dStack.size() - 1);

	return true;
}

bool CB3DMeshFileLoader::readChunkMESH(CSkinnedMesh::SJoint *inJoint)
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "read ChunkMESH";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	s32 brushID;
	B3DFile->read(&brushID, sizeof(brushID));
#ifdef __BIG_ENDIAN__
	brushID = os::Byteswap::byteswap(brushID);
#endif

	NormalsInFile = false;
	HasVertexColors = false;

	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
	{
		SB3dChunkHeader header;
		B3DFile->read(&header, sizeof(header));
#ifdef __BIG_ENDIAN__
		header.size = os::Byteswap::byteswap(header.size);
#endif

		B3dStack.push_back(SB3dChunk(header, B3DFile->getPos() - 8));

		if (strncmp(B3dStack.getLast().name, "VRTS", 4) == 0) {
			if (!readChunkVRTS(inJoint))
				return false;
		} else if (strncmp(B3dStack.getLast().name, "TRIS", 4) == 0) {
			scene::SSkinMeshBuffer *meshBuffer = AnimatedMesh->addMeshBuffer();

			if (brushID == -1) { /* ok */
			} else if (brushID < 0 || (u32)brushID >= Materials.size()) {
				os::Printer::log("Illegal brush ID found", B3DFile->getFileName(), ELL_ERROR);
				return false;
			} else {
				meshBuffer->Material = Materials[brushID].Material;
			}

			if (readChunkTRIS(meshBuffer, AnimatedMesh->getMeshBuffers().size() - 1, VerticesStart) == false)
				return false;

			if (!NormalsInFile) {
				s32 i;

				auto &indices = meshBuffer->Indices->Data;
				for (i = 0; i < (s32)indices.size(); i += 3) {
					core::plane3df p(meshBuffer->getVertex(indices[i + 0])->Pos,
							meshBuffer->getVertex(indices[i + 1])->Pos,
							meshBuffer->getVertex(indices[i + 2])->Pos);

					meshBuffer->getVertex(indices[i + 0])->Normal += p.Normal;
					meshBuffer->getVertex(indices[i + 1])->Normal += p.Normal;
					meshBuffer->getVertex(indices[i + 2])->Normal += p.Normal;
				}

				for (i = 0; i < (s32)meshBuffer->getVertexCount(); ++i) {
					meshBuffer->getVertex(i)->Normal.normalize();
					BaseVertices[VerticesStart + i].Normal = meshBuffer->getVertex(i)->Normal;
				}
			}
		} else {
			os::Printer::log("Unknown chunk found in mesh - skipping");
			if (!B3DFile->seek(B3dStack.getLast().startposition + B3dStack.getLast().length))
				return false;
			B3dStack.erase(B3dStack.size() - 1);
		}
	}

	B3dStack.erase(B3dStack.size() - 1);

	return true;
}

/*
VRTS:
  int flags                   ;1=normal values present, 2=rgba values present
  int tex_coord_sets          ;texture coords per vertex (eg: 1 for simple U/V) max=8
				but we only support 3
  int tex_coord_set_size      ;components per set (eg: 2 for simple U/V) max=4
  {
  float x,y,z                 ;always present
  float nx,ny,nz              ;vertex normal: present if (flags&1)
  float red,green,blue,alpha  ;vertex color: present if (flags&2)
  float tex_coords[tex_coord_sets][tex_coord_set_size]	;tex coords
  }
*/
bool CB3DMeshFileLoader::readChunkVRTS(CSkinnedMesh::SJoint *inJoint)
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "ChunkVRTS";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	const s32 max_tex_coords = 3;
	s32 flags, tex_coord_sets, tex_coord_set_size;

	B3DFile->read(&flags, sizeof(flags));
	B3DFile->read(&tex_coord_sets, sizeof(tex_coord_sets));
	B3DFile->read(&tex_coord_set_size, sizeof(tex_coord_set_size));
#ifdef __BIG_ENDIAN__
	flags = os::Byteswap::byteswap(flags);
	tex_coord_sets = os::Byteswap::byteswap(tex_coord_sets);
	tex_coord_set_size = os::Byteswap::byteswap(tex_coord_set_size);
#endif

	if (tex_coord_sets < 0 || tex_coord_set_size < 0 ||
			tex_coord_sets >= max_tex_coords || tex_coord_set_size >= 4) // Something is wrong
	{
		os::Printer::log("tex_coord_sets or tex_coord_set_size too big", B3DFile->getFileName(), ELL_ERROR);
		return false;
	}

	//------ Allocate Memory, for speed -----------//

	s32 numberOfReads = 3;

	if (flags & 1) {
		NormalsInFile = true;
		numberOfReads += 3;
	}
	if (flags & 2) {
		numberOfReads += 4;
		HasVertexColors = true;
	}

	numberOfReads += tex_coord_sets * tex_coord_set_size;

	const s32 memoryNeeded = (B3dStack.getLast().length / sizeof(f32)) / numberOfReads;

	BaseVertices.reallocate(memoryNeeded + BaseVertices.size() + 1);
	AnimatedVertices_VertexID.reallocate(memoryNeeded + AnimatedVertices_VertexID.size() + 1);

	//--------------------------------------------//

	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
	{
		f32 position[3];
		f32 normal[3] = {0.f, 0.f, 0.f};
		f32 color[4] = {1.0f, 1.0f, 1.0f, 1.0f};
		f32 tex_coords[max_tex_coords][4];

		readFloats(position, 3);

		if (flags & 1)
			readFloats(normal, 3);
		if (flags & 2)
			readFloats(color, 4);

		for (s32 i = 0; i < tex_coord_sets; ++i)
			readFloats(tex_coords[i], tex_coord_set_size);

		f32 tu = 0.0f, tv = 0.0f;
		if (tex_coord_sets >= 1 && tex_coord_set_size >= 2) {
			tu = tex_coords[0][0];
			tv = tex_coords[0][1];
		}

		f32 tu2 = 0.0f, tv2 = 0.0f;
		if (tex_coord_sets > 1 && tex_coord_set_size > 1) {
			tu2 = tex_coords[1][0];
			tv2 = tex_coords[1][1];
		}

		// Create Vertex...
		video::S3DVertex2TCoords Vertex(position[0], position[1], position[2],
				normal[0], normal[1], normal[2],
				video::SColorf(color[0], color[1], color[2], color[3]).toSColor(),
				tu, tv, tu2, tv2);

		// Transform the Vertex position by nested node...
		inJoint->GlobalMatrix.transformVect(Vertex.Pos);
		Vertex.Normal = inJoint->GlobalMatrix.rotateAndScaleVect(Vertex.Normal);
		Vertex.Normal.normalize(); // renormalize: normal might have been skewed by scaling

		// Add it...
		BaseVertices.push_back(Vertex);

		AnimatedVertices_VertexID.push_back(-1);
		AnimatedVertices_BufferID.push_back(-1);
	}

	B3dStack.erase(B3dStack.size() - 1);

	return true;
}

bool CB3DMeshFileLoader::readChunkTRIS(scene::SSkinMeshBuffer *meshBuffer, u32 meshBufferID, s32 vertices_Start)
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "ChunkTRIS";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	bool showVertexWarning = false;

	s32 triangle_brush_id; // Note: Irrlicht can't have different brushes for each triangle (using a workaround)
	B3DFile->read(&triangle_brush_id, sizeof(triangle_brush_id));
#ifdef __BIG_ENDIAN__
	triangle_brush_id = os::Byteswap::byteswap(triangle_brush_id);
#endif

	SB3dMaterial *B3dMaterial;

	if (triangle_brush_id == -1)
		B3dMaterial = 0;
	else if (triangle_brush_id < 0 || (u32)triangle_brush_id >= Materials.size()) {
		os::Printer::log("Illegal material index found", B3DFile->getFileName(), ELL_ERROR);
		return false;
	} else {
		B3dMaterial = &Materials[triangle_brush_id];
		meshBuffer->Material = B3dMaterial->Material;
	}

	const s32 memoryNeeded = B3dStack.getLast().length / sizeof(s32);
	meshBuffer->Indices->Data.reserve(memoryNeeded + meshBuffer->Indices->Data.size() + 1);

	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
	{
		s32 vertex_id[3];

		B3DFile->read(vertex_id, 3 * sizeof(s32));
#ifdef __BIG_ENDIAN__
		vertex_id[0] = os::Byteswap::byteswap(vertex_id[0]);
		vertex_id[1] = os::Byteswap::byteswap(vertex_id[1]);
		vertex_id[2] = os::Byteswap::byteswap(vertex_id[2]);
#endif

		// Make Ids global:
		vertex_id[0] += vertices_Start;
		vertex_id[1] += vertices_Start;
		vertex_id[2] += vertices_Start;

		for (s32 i = 0; i < 3; ++i) {
			if ((u32)vertex_id[i] >= AnimatedVertices_VertexID.size()) {
				os::Printer::log("Illegal vertex index found", B3DFile->getFileName(), ELL_ERROR);
				return false;
			}

			if (AnimatedVertices_VertexID[vertex_id[i]] != -1) {
				if (AnimatedVertices_BufferID[vertex_id[i]] != (s32)meshBufferID) { // If this vertex is linked in a different meshbuffer
					AnimatedVertices_VertexID[vertex_id[i]] = -1;
					AnimatedVertices_BufferID[vertex_id[i]] = -1;
					showVertexWarning = true;
				}
			}
			if (AnimatedVertices_VertexID[vertex_id[i]] == -1) { // If this vertex is not in the meshbuffer
				// Check for lightmapping:
				if (BaseVertices[vertex_id[i]].TCoords2 != core::vector2df(0.f, 0.f))
					meshBuffer->convertTo2TCoords(); // Will only affect the meshbuffer the first time this is called

				// Add the vertex to the meshbuffer:
				if (meshBuffer->VertexType == video::EVT_STANDARD)
					meshBuffer->Vertices_Standard->Data.push_back(BaseVertices[vertex_id[i]]);
				else
					meshBuffer->Vertices_2TCoords->Data.push_back(BaseVertices[vertex_id[i]]);

				// create vertex id to meshbuffer index link:
				AnimatedVertices_VertexID[vertex_id[i]] = meshBuffer->getVertexCount() - 1;
				AnimatedVertices_BufferID[vertex_id[i]] = meshBufferID;

				if (B3dMaterial) {
					// Apply Material/Color/etc...
					video::S3DVertex *Vertex = meshBuffer->getVertex(meshBuffer->getVertexCount() - 1);

					if (!HasVertexColors)
						Vertex->Color = video::SColorf(B3dMaterial->red, B3dMaterial->green,
								B3dMaterial->blue, B3dMaterial->alpha).toSColor();
					else if (Vertex->Color.getAlpha() == 255)
						Vertex->Color.setAlpha((s32)(B3dMaterial->alpha * 255.0f));

					// Use texture's scale
					if (B3dMaterial->Textures[0]) {
						Vertex->TCoords.X *= B3dMaterial->Textures[0]->Xscale;
						Vertex->TCoords.Y *= B3dMaterial->Textures[0]->Yscale;
					}
					/*
					if (B3dMaterial->Textures[1])
					{
						Vertex->TCoords2.X *=B3dMaterial->Textures[1]->Xscale;
						Vertex->TCoords2.Y *=B3dMaterial->Textures[1]->Yscale;
					}
					*/
				}
			}
		}

		meshBuffer->Indices->Data.push_back(AnimatedVertices_VertexID[vertex_id[0]]);
		meshBuffer->Indices->Data.push_back(AnimatedVertices_VertexID[vertex_id[1]]);
		meshBuffer->Indices->Data.push_back(AnimatedVertices_VertexID[vertex_id[2]]);
	}

	B3dStack.erase(B3dStack.size() - 1);

	if (showVertexWarning)
		os::Printer::log("B3dMeshLoader: Warning, different meshbuffers linking to the same vertex, this will cause problems with animated meshes");

	return true;
}

bool CB3DMeshFileLoader::readChunkBONE(CSkinnedMesh::SJoint *inJoint)
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "read ChunkBONE";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	if (B3dStack.getLast().length > 8) {
		while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
		{
			u32 globalVertexID;
			f32 strength;
			B3DFile->read(&globalVertexID, sizeof(globalVertexID));
			B3DFile->read(&strength, sizeof(strength));
#ifdef __BIG_ENDIAN__
			globalVertexID = os::Byteswap::byteswap(globalVertexID);
			strength = os::Byteswap::byteswap(strength);
#endif
			globalVertexID += VerticesStart;

			if (globalVertexID >= AnimatedVertices_VertexID.size()) {
				os::Printer::log("Illegal vertex index found", B3DFile->getFileName(), ELL_ERROR);
				return false;
			}

			if (AnimatedVertices_VertexID[globalVertexID] == -1) {
				os::Printer::log("B3dMeshLoader: Weight has bad vertex id (no link to meshbuffer index found)");
			} else if (strength > 0) {
				CSkinnedMesh::SWeight *weight = AnimatedMesh->addWeight(inJoint);
				weight->strength = strength;
				// Find the meshbuffer and Vertex index from the Global Vertex ID:
				weight->vertex_id = AnimatedVertices_VertexID[globalVertexID];
				weight->buffer_id = AnimatedVertices_BufferID[globalVertexID];
			}
		}
	}

	B3dStack.erase(B3dStack.size() - 1);
	return true;
}

bool CB3DMeshFileLoader::readChunkKEYS(CSkinnedMesh::SJoint *inJoint)
{
#ifdef _B3D_READER_DEBUG
	// Only print first, that's just too much output otherwise
	if (!inJoint || (inJoint->PositionKeys.empty() && inJoint->ScaleKeys.empty() && inJoint->RotationKeys.empty())) {
		core::stringc logStr;
		for (u32 i = 1; i < B3dStack.size(); ++i)
			logStr += "-";
		logStr += "read ChunkKEYS";
		os::Printer::log(logStr.c_str(), ELL_DEBUG);
	}
#endif

	s32 flags;
	B3DFile->read(&flags, sizeof(flags));
#ifdef __BIG_ENDIAN__
	flags = os::Byteswap::byteswap(flags);
#endif

	CSkinnedMesh::SPositionKey *oldPosKey = 0;
	core::vector3df oldPos[2];
	CSkinnedMesh::SScaleKey *oldScaleKey = 0;
	core::vector3df oldScale[2];
	CSkinnedMesh::SRotationKey *oldRotKey = 0;
	core::quaternion oldRot[2];
	bool isFirst[3] = {true, true, true};
	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
	{
		s32 frame;

		B3DFile->read(&frame, sizeof(frame));
#ifdef __BIG_ENDIAN__
		frame = os::Byteswap::byteswap(frame);
#endif

		// Add key frames, frames in Irrlicht are zero-based
		f32 data[4];
		if (flags & 1) {
			readFloats(data, 3);
			if ((oldPosKey != 0) && (oldPos[0] == oldPos[1])) {
				const core::vector3df pos(data[0], data[1], data[2]);
				if (oldPos[1] == pos)
					oldPosKey->frame = (f32)frame - 1;
				else {
					oldPos[0] = oldPos[1];
					oldPosKey = AnimatedMesh->addPositionKey(inJoint);
					oldPosKey->frame = (f32)frame - 1;
					oldPos[1].set(oldPosKey->position.set(pos));
				}
			} else if (oldPosKey == 0 && isFirst[0]) {
				oldPosKey = AnimatedMesh->addPositionKey(inJoint);
				oldPosKey->frame = (f32)frame - 1;
				oldPos[0].set(oldPosKey->position.set(data[0], data[1], data[2]));
				oldPosKey = 0;
				isFirst[0] = false;
			} else {
				if (oldPosKey != 0)
					oldPos[0] = oldPos[1];
				oldPosKey = AnimatedMesh->addPositionKey(inJoint);
				oldPosKey->frame = (f32)frame - 1;
				oldPos[1].set(oldPosKey->position.set(data[0], data[1], data[2]));
			}
		}
		if (flags & 2) {
			readFloats(data, 3);
			if ((oldScaleKey != 0) && (oldScale[0] == oldScale[1])) {
				const core::vector3df scale(data[0], data[1], data[2]);
				if (oldScale[1] == scale)
					oldScaleKey->frame = (f32)frame - 1;
				else {
					oldScale[0] = oldScale[1];
					oldScaleKey = AnimatedMesh->addScaleKey(inJoint);
					oldScaleKey->frame = (f32)frame - 1;
					oldScale[1].set(oldScaleKey->scale.set(scale));
				}
			} else if (oldScaleKey == 0 && isFirst[1]) {
				oldScaleKey = AnimatedMesh->addScaleKey(inJoint);
				oldScaleKey->frame = (f32)frame - 1;
				oldScale[0].set(oldScaleKey->scale.set(data[0], data[1], data[2]));
				oldScaleKey = 0;
				isFirst[1] = false;
			} else {
				if (oldScaleKey != 0)
					oldScale[0] = oldScale[1];
				oldScaleKey = AnimatedMesh->addScaleKey(inJoint);
				oldScaleKey->frame = (f32)frame - 1;
				oldScale[1].set(oldScaleKey->scale.set(data[0], data[1], data[2]));
			}
		}
		if (flags & 4) {
			readFloats(data, 4);
			if ((oldRotKey != 0) && (oldRot[0] == oldRot[1])) {
				// meant to be in this order since b3d stores W first
				const core::quaternion rot(data[1], data[2], data[3], data[0]);
				if (oldRot[1] == rot)
					oldRotKey->frame = (f32)frame - 1;
				else {
					oldRot[0] = oldRot[1];
					oldRotKey = AnimatedMesh->addRotationKey(inJoint);
					oldRotKey->frame = (f32)frame - 1;
					oldRot[1].set(oldRotKey->rotation.set(data[1], data[2], data[3], data[0]));
					oldRot[1].normalize();
				}
			} else if (oldRotKey == 0 && isFirst[2]) {
				oldRotKey = AnimatedMesh->addRotationKey(inJoint);
				oldRotKey->frame = (f32)frame - 1;
				// meant to be in this order since b3d stores W first
				oldRot[0].set(oldRotKey->rotation.set(data[1], data[2], data[3], data[0]));
				oldRot[0].normalize();
				oldRotKey = 0;
				isFirst[2] = false;
			} else {
				if (oldRotKey != 0)
					oldRot[0] = oldRot[1];
				oldRotKey = AnimatedMesh->addRotationKey(inJoint);
				oldRotKey->frame = (f32)frame - 1;
				// meant to be in this order since b3d stores W first
				oldRot[1].set(oldRotKey->rotation.set(data[1], data[2], data[3], data[0]));
				oldRot[1].normalize();
			}
		}
	}

	B3dStack.erase(B3dStack.size() - 1);
	return true;
}

bool CB3DMeshFileLoader::readChunkANIM()
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "read ChunkANIM";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	s32 animFlags;  // not stored\used
	s32 animFrames; // not stored\used
	f32 animFPS;    // not stored\used

	B3DFile->read(&animFlags, sizeof(s32));
	B3DFile->read(&animFrames, sizeof(s32));
	readFloats(&animFPS, 1);
	if (animFPS > 0.f)
		AnimatedMesh->setAnimationSpeed(animFPS);
	os::Printer::log("FPS", io::path((double)animFPS), ELL_DEBUG);

#ifdef __BIG_ENDIAN__
	animFlags = os::Byteswap::byteswap(animFlags);
	animFrames = os::Byteswap::byteswap(animFrames);
#endif

	B3dStack.erase(B3dStack.size() - 1);
	return true;
}

bool CB3DMeshFileLoader::readChunkTEXS()
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "read ChunkTEXS";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
	{
		Textures.push_back(SB3dTexture());
		SB3dTexture &B3dTexture = Textures.getLast();

		B3dTexture.TextureName = readString();
		std::replace(B3dTexture.TextureName.begin(), B3dTexture.TextureName.end(), '\\', '/');
#ifdef _B3D_READER_DEBUG
		os::Printer::log("read Texture", B3dTexture.TextureName.c_str(), ELL_DEBUG);
#endif

		B3DFile->read(&B3dTexture.Flags, sizeof(s32));
		B3DFile->read(&B3dTexture.Blend, sizeof(s32));
#ifdef __BIG_ENDIAN__
		B3dTexture.Flags = os::Byteswap::byteswap(B3dTexture.Flags);
		B3dTexture.Blend = os::Byteswap::byteswap(B3dTexture.Blend);
#endif
#ifdef _B3D_READER_DEBUG
		os::Printer::log("Flags", core::stringc(B3dTexture.Flags).c_str(), ELL_DEBUG);
		os::Printer::log("Blend", core::stringc(B3dTexture.Blend).c_str(), ELL_DEBUG);
#endif
		readFloats(&B3dTexture.Xpos, 1);
		readFloats(&B3dTexture.Ypos, 1);
		readFloats(&B3dTexture.Xscale, 1);
		readFloats(&B3dTexture.Yscale, 1);
		readFloats(&B3dTexture.Angle, 1);
	}

	B3dStack.erase(B3dStack.size() - 1);

	return true;
}

bool CB3DMeshFileLoader::readChunkBRUS()
{
#ifdef _B3D_READER_DEBUG
	core::stringc logStr;
	for (u32 i = 1; i < B3dStack.size(); ++i)
		logStr += "-";
	logStr += "read ChunkBRUS";
	os::Printer::log(logStr.c_str(), ELL_DEBUG);
#endif

	u32 n_texs;
	B3DFile->read(&n_texs, sizeof(u32));
#ifdef __BIG_ENDIAN__
	n_texs = os::Byteswap::byteswap(n_texs);
#endif

	// number of texture ids read for Irrlicht
	const u32 num_textures = core::min_(n_texs, video::MATERIAL_MAX_TEXTURES);
	// number of bytes to skip (for ignored texture ids)
	const u32 n_texs_offset = (num_textures < n_texs) ? (n_texs - num_textures) : 0;

	while ((B3dStack.getLast().startposition + B3dStack.getLast().length) > B3DFile->getPos()) // this chunk repeats
	{
		// This is what blitz basic calls a brush, like a Irrlicht Material

		auto name = readString();
#ifdef _B3D_READER_DEBUG
		os::Printer::log("read Material", name.c_str(), ELL_DEBUG);
#endif
		Materials.push_back(SB3dMaterial());
		SB3dMaterial &B3dMaterial = Materials.getLast();

		readFloats(&B3dMaterial.red, 1);
		readFloats(&B3dMaterial.green, 1);
		readFloats(&B3dMaterial.blue, 1);
		readFloats(&B3dMaterial.alpha, 1);
		readFloats(&B3dMaterial.shininess, 1);

		B3DFile->read(&B3dMaterial.blend, sizeof(B3dMaterial.blend));
		B3DFile->read(&B3dMaterial.fx, sizeof(B3dMaterial.fx));
#ifdef __BIG_ENDIAN__
		B3dMaterial.blend = os::Byteswap::byteswap(B3dMaterial.blend);
		B3dMaterial.fx = os::Byteswap::byteswap(B3dMaterial.fx);
#endif
#ifdef _B3D_READER_DEBUG
		os::Printer::log("Blend", core::stringc(B3dMaterial.blend).c_str(), ELL_DEBUG);
		os::Printer::log("FX", core::stringc(B3dMaterial.fx).c_str(), ELL_DEBUG);
#endif

		u32 i;
		for (i = 0; i < num_textures; ++i) {
			s32 texture_id = -1;
			B3DFile->read(&texture_id, sizeof(s32));
#ifdef __BIG_ENDIAN__
			texture_id = os::Byteswap::byteswap(texture_id);
#endif
			//--- Get pointers to the texture, based on the IDs ---
			if ((u32)texture_id < Textures.size()) {
				B3dMaterial.Textures[i] = &Textures[texture_id];
#ifdef _B3D_READER_DEBUG
				os::Printer::log("Layer", core::stringc(i).c_str(), ELL_DEBUG);
				os::Printer::log("using texture", Textures[texture_id].TextureName.c_str(), ELL_DEBUG);
#endif
			} else
				B3dMaterial.Textures[i] = 0;
		}
		// skip other texture ids
		for (i = 0; i < n_texs_offset; ++i) {
			s32 texture_id = -1;
			B3DFile->read(&texture_id, sizeof(s32));
#ifdef __BIG_ENDIAN__
			texture_id = os::Byteswap::byteswap(texture_id);
#endif
			if (ShowWarning && (texture_id != -1) && (n_texs > video::MATERIAL_MAX_TEXTURES)) {
				os::Printer::log("Too many textures used in one material", B3DFile->getFileName(), ELL_WARNING);
				ShowWarning = false;
			}
		}

		// Fixes problems when the lightmap is on the first texture:
		if (B3dMaterial.Textures[0] != 0) {
			if (B3dMaterial.Textures[0]->Flags & 65536) { // 65536 = secondary UV
				SB3dTexture *TmpTexture;
				TmpTexture = B3dMaterial.Textures[1];
				B3dMaterial.Textures[1] = B3dMaterial.Textures[0];
				B3dMaterial.Textures[0] = TmpTexture;
			}
		}

		// If a preceeding texture slot is empty move the others down:
		for (i = num_textures; i > 0; --i) {
			for (u32 j = i - 1; j < num_textures - 1; ++j) {
				if (B3dMaterial.Textures[j + 1] != 0 && B3dMaterial.Textures[j] == 0) {
					B3dMaterial.Textures[j] = B3dMaterial.Textures[j + 1];
					B3dMaterial.Textures[j + 1] = 0;
				}
			}
		}

		//------ Convert blitz flags/blend to irrlicht -------

		// Two textures:
		if (B3dMaterial.Textures[1]) {
			B3dMaterial.Material.MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
			B3dMaterial.Material.ZWriteEnable = video::EZW_OFF;
		} else if (B3dMaterial.Textures[0]) { // One texture:
			// Flags & 0x1 is usual SOLID, 0x8 is mipmap (handled before)
			if (B3dMaterial.Textures[0]->Flags & 0x2) { // (Alpha mapped)
				B3dMaterial.Material.MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL;
				B3dMaterial.Material.ZWriteEnable = video::EZW_OFF;
			} else if (B3dMaterial.Textures[0]->Flags & 0x4)                                  //(Masked)
				B3dMaterial.Material.MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL_REF; // TODO: create color key texture
			else if (B3dMaterial.alpha == 1.f)
				B3dMaterial.Material.MaterialType = video::EMT_SOLID;
			else {
				B3dMaterial.Material.MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
				B3dMaterial.Material.ZWriteEnable = video::EZW_OFF;
			}
		} else // No texture:
		{
			if (B3dMaterial.alpha == 1.f)
				B3dMaterial.Material.MaterialType = video::EMT_SOLID;
			else {
				B3dMaterial.Material.MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
				B3dMaterial.Material.ZWriteEnable = video::EZW_OFF;
			}
		}

		//------ Material fx ------

		if (B3dMaterial.fx & 16) // disable backface culling
			B3dMaterial.Material.BackfaceCulling = false;

		if (B3dMaterial.fx & 32) { // force vertex alpha-blending
			B3dMaterial.Material.MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
			B3dMaterial.Material.ZWriteEnable = video::EZW_OFF;
		}
	}

	B3dStack.erase(B3dStack.size() - 1);

	return true;
}

std::string CB3DMeshFileLoader::readString()
{
	std::string newstring = "";
	while (true) {
		c8 character;
		if (B3DFile->read(&character, sizeof(character)) == 0)
			break; // eof
		if (character == 0)
			break;
		newstring.push_back(character);
	}
	return newstring;
}

void CB3DMeshFileLoader::readFloats(f32 *vec, u32 count)
{
	B3DFile->read(vec, count * sizeof(f32));
#ifdef __BIG_ENDIAN__
	for (u32 n = 0; n < count; ++n)
		vec[n] = os::Byteswap::byteswap(vec[n]);
#endif
}

} // end namespace scene
} // end namespace irr