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Where else are you going to keep your 3D data?...

3DS Part 3- "Our Shapes Our Here" - Finally

by bkenwright@xbdev.net

With some final tweaking here and there, we can get our colours and texture details for our shapes, and we'll have all our 3D file information (excluding the animations - but we'll get to that later).

0xafff is our material ...which upto now we've ignored...so if we want our materials...which means colours...we'll need to go into that chunk.

Certain things to look for are nested Chunks...as you'll notice that at the bottom of some function calls, there's a SkipChunk(...) function. So if there are any nested chunks in there, they will be skipped.

So how do we go about reading our materials in? Well thats why where reading this..heheh

Now the materials are stored in a seperate list, and so there is a group of materials and they are loaded in, then our objects...3d meshes etc, just reference these materials using there name.

Reading in the list of materials is done by first adding to our code:

///////////////////////////////////////////////////////////////////////0x3D3D

void ReadEDIT3DS(FILE *fp, stChunk* Chunk)

{

abc("\n");

while(Chunk->bytesRead < Chunk->length)

{

stChunk tempChunk = {0};

ReadChunk(fp, &tempChunk);

DisplayChunkInfo(&tempChunk);

switch( tempChunk.ID)

{

// NEW* NEW * NEW * NEW * NEW * NEW *

case MATERIAL:

ReadMATERIAL(fp, &tempChunk);

break;

// NEW* NEW * NEW * NEW * NEW * NEW *

case NAMED_OBJECT:

ReadNAMED_OBJECT(fp, &tempChunk);

break;

default:

SkipChunk(fp, &tempChunk);

}

Chunk->bytesRead += tempChunk.length;

}

Now we've added a new sub-section, which reads in all our materials. This new function has a nice easy name, ReadMATERIAL(...).

This new functions read in our <*>Diffuse Colour <*>Material Name <*>File Name (if there is one). Below shows the files that read in the material information.

///////////////////////////////////////////////////////////////////////0xAFFF

void ReadMATERIAL(FILE *fp, stChunk* Chunk)

{

abc("\n");

while(Chunk->bytesRead < Chunk->length)

{

stChunk tempChunk = {0};

ReadChunk(fp, &tempChunk);

DisplayChunkInfo(&tempChunk);

switch( tempChunk.ID)

{

case MAT_NAME: //0xA000 - sz for hte material name "e.g. default 2"

Chunk->bytesRead += GetString(fp);

break;

// Each object...has a material set to it!.. .in order, so first

// object is the first material etc.

case MAT_DIFFUSE: // Diffuse Colour //0xa020

ReadMATDIFFUSE(fp, &tempChunk);

break;

// MAT_TEXMAP calls itself here. (recursive call)

case MAT_TEXMAP: // if there's a texture wrapped to it where here

ReadMATERIAL(fp, &tempChunk);

break;

case MAT_TEXFLNM: // get filename of the material

Chunk->bytesRead += GetString(fp);

break;

default:

SkipChunk(fp, &tempChunk);

}

Chunk->bytesRead += tempChunk.length;

}

///////////////////////////////////////////////////////////////////////0xA020

void ReadMATDIFFUSE(FILE *fp, stChunk* Chunk)

{

abc("\n");

struct stRGB{ unsigned char r, g, b; };

stRGB DiffColour;

char ChunkHeader[6];

Chunk->bytesRead += fread(ChunkHeader, 1, 6, fp);

Chunk->bytesRead += fread(&DiffColour, 1, 3, fp);

// e.g. Display our diffuse colour we read in

char buff[300];

sprintf(buff, "Diffuse Colour\t r: %x g: %x b: %x\n",

DiffColour.r, DiffColour.g, DiffColour.b);

abc(buff);

SkipChunk(fp, Chunk);

}

Well we have our materials, but now we have to apply it to our shapes! As each shape has saves which face uses which Material name. So as we load in each object we have to compare it with the list of Materials we've loaded in.

I've cut the section of code that loads our object into the world below.....

///////////////////////////////////////////////////////////////////////0x4100

void LoadMeshOBJ_MESH(FILE *fp, stChunk* Chunk)

{

abc("\n");

while(Chunk->bytesRead < Chunk->length)

{

stChunk tempChunk = {0};

ReadChunk(fp, &tempChunk);

DisplayChunkInfo(&tempChunk);

switch( tempChunk.ID)

{

case MESH_VERTICES:

ReadVerticesMESH_VERTICES(fp, &tempChunk);

break;

case MESH_FACES:

ReadVertRefsMESH_FACES(fp, &tempChunk);

break;

case MESH_TEX_VERT:

ReadTEXVERTS(fp, &tempChunk);

break;

case MESH_MATER:

ReadMESHMATERIAL(fp, &tempChunk);

break;

default:

SkipChunk(fp, &tempChunk);

}

Chunk->bytesRead += tempChunk.length;

}

///////////////////////////////////////////////////////////////////////0x4130

void ReadMESHMATERIAL(FILE *fp, stChunk* Chunk)

{

abc("\n");

// Material Name Where Referencing

unsigned int characterlen = GetString(fp);

Chunk->bytesRead += characterlen;

unsigned short iNumFaces = 0;

Chunk->bytesRead += fread(&iNumFaces, 1, 2, fp);

unsigned short *FaceAssignedThisMaterial = new unsigned short[iNumFaces];

Chunk->bytesRead += fread(FaceAssignedThisMaterial, 1,

iNumFaces*sizeof(unsigned short), fp);

char buf[1000] = {0};

sprintf(buf, "Material: FaceCount: %d\n",iNumFaces);

abc(buf);

for( int i=0; i<iNumFaces; i++ )

{

sprintf(buf, "\tFaceAssignedThisMaterial: %d\n",FaceAssignedThisMaterial[i]);

abc(buf);

}

return;

}

void LoadMeshOBJ_MESH(FILE *fp, stChunk* Chunk); // Forward declaration

///////////////////////////////////////////////////////////////////////0x4120

void ReadVertRefsMESH_FACES(FILE *fp, stChunk* Chunk)

{

unsigned int iNumberFaces = 0; //= Chunk->length - 6;

Chunk->bytesRead += fread(&iNumberFaces, 1, 2, fp);

char buff[100];

sprintf(buff, "Number of Faces %u\n", iNumberFaces);

abc(buff);

// Each face is 3 points A TRIANGLE!..WOW

struct stFace{ unsigned short p1, p2, p3, visibityflag; };

stFace *pFaces = new stFace[iNumberFaces];

Chunk->bytesRead += fread(pFaces, 1, iNumberFaces*sizeof(stFace), fp);

for( int i=0; i<iNumberFaces; i++ )

{

sprintf(buff, "\t Face: Index1: %d, Index2: %d, Index3 %d\n",

pFaces[i].p1, pFaces[i].p2, pFaces[i].p3);

abc(buff);

}

delete pFaces;

// Our face material information is a sub-chunk.

LoadMeshOBJ_MESH( fp, Chunk );

}

///////////////////////////////////////////////////////////////////////0x4110

void ReadVerticesMESH_VERTICES(FILE *fp, stChunk* Chunk)

{

unsigned int iNumberVertices = 0;

Chunk->bytesRead += fread(&iNumberVertices, 1, 2, fp);

// e.g. 8 Vertices make up our simple box!

char buff[300];

sprintf(buff, "Number of Vertices %d\n", iNumberVertices);

abc(buff);

// Allocate Memory and dump our vertices to the screen.

struct stVect{ float x, y, z; };

stVect *pVerts = new stVect[iNumberVertices];

Chunk->bytesRead += fread( (void*)pVerts, 1, iNumberVertices*sizeof(stVect), fp);

for(int i=0; i<iNumberVertices; i++)

{

sprintf(buff, "\t Vertices Point: x: %.2f, \ty: %.2f, \tz: %.2f\n",

pVerts[i].x, pVerts[i].y, pVerts[i].z);

abc(buff);

}

delete[] pVerts;

SkipChunk(fp, Chunk);

}

///////////////////////////////////////////////////////////////////////0x4140

void ReadTEXVERTS(FILE *fp, stChunk* Chunk)

{

unsigned short iNumberVertices = 0;

Chunk->bytesRead += fread(&iNumberVertices, 1, 2, fp);

// e.g. 8 Vertices make up our simple box!

char buff[300];

sprintf(buff, "Number of Vertices %d\n", iNumberVertices);

abc(buff);

// Allocate Memory and dump our texture for each vertice to the screen.

struct stTex{ float tu, tv; };

stTex *pTex = new stTex[iNumberVertices];

Chunk->bytesRead += fread( (void*)pTex, 1, iNumberVertices*sizeof(stTex), fp);

for(int i=0; i<iNumberVertices; i++)

{

sprintf(buff, "\t Tex Coord: tu: %.2f, \t tv: %.2f\n",

pTex[i].tu, pTex[i].tv);

abc(buff);

}

delete[] pTex;

SkipChunk(fp, Chunk);

}

Using the output shown below you should be able to see the data that we've managed to extract...which is a lot! If you notice, we have all the vertice (x,y,z things) and the texture/colour information. Note that I've ignored a lot of the texture information, as I only think its necessary to load in the diffuse colour information...but if you wanted to you load in others...specular (0xa020) etc

Chunk ID: 0x 4d4d Size of Chunk: 1417

Chunk ID: 0x 0002 Size of Chunk: 10

Chunk ID: 0x 3d3d Size of Chunk: 1182

Chunk ID: 0x 3d3e Size of Chunk: 10

Chunk ID: 0x afff Size of Chunk: 226

Chunk ID: 0x a000 Size of Chunk: 18

8 - Default

Chunk ID: 0x a010 Size of Chunk: 15

Chunk ID: 0x a020 Size of Chunk: 15

Diffuse Colour r: ff g: 96 b: 96

Chunk ID: 0x a030 Size of Chunk: 15

Chunk ID: 0x a040 Size of Chunk: 14

Chunk ID: 0x a041 Size of Chunk: 14

Chunk ID: 0x a050 Size of Chunk: 14

Chunk ID: 0x a052 Size of Chunk: 14

Chunk ID: 0x a053 Size of Chunk: 14

Chunk ID: 0x a100 Size of Chunk: 8

Chunk ID: 0x a084 Size of Chunk: 14

Chunk ID: 0x a08a Size of Chunk: 6

Chunk ID: 0x a087 Size of Chunk: 10

Chunk ID: 0x a200 Size of Chunk: 49

Chunk ID: 0x 0030 Size of Chunk: 8

Chunk ID: 0x a300 Size of Chunk: 17

OCTREE.JPG

Chunk ID: 0x a351 Size of Chunk: 8

Chunk ID: 0x a353 Size of Chunk: 10

Chunk ID: 0x 0100 Size of Chunk: 10

Chunk ID: 0x 4000 Size of Chunk: 930

Box03

Chunk ID: 0x 4100 Size of Chunk: 918

Chunk ID: 0x 4110 Size of Chunk: 392

Number of Vertices 32

Vertices Point: x: -6.79, y: -2.30, z: 0.00

Vertices Point: x: -2.93, y: -2.30, z: 0.00

Vertices Point: x: -6.79, y: 5.29, z: 0.00

Vertices Point: x: -2.93, y: 5.29, z: 0.00

Vertices Point: x: -6.79, y: -2.30, z: 4.13

Vertices Point: x: -2.93, y: -2.30, z: 4.13

Vertices Point: x: -6.79, y: 5.29, z: 4.13

Vertices Point: x: -2.93, y: 5.29, z: 4.13

Vertices Point: x: -6.79, y: -2.30, z: 0.00

Vertices Point: x: -2.93, y: -2.30, z: 0.00

Vertices Point: x: -2.93, y: -2.30, z: 4.13

Vertices Point: x: -6.79, y: -2.30, z: 4.13

Vertices Point: x: -6.79, y: -2.30, z: 0.00

Vertices Point: x: -2.93, y: -2.30, z: 0.00

Vertices Point: x: -2.93, y: 5.29, z: 0.00

Vertices Point: x: -2.93, y: 5.29, z: 4.13

Vertices Point: x: -2.93, y: -2.30, z: 4.13

Vertices Point: x: -2.93, y: -2.30, z: 0.00

Vertices Point: x: -2.93, y: 5.29, z: 0.00

Vertices Point: x: -6.79, y: 5.29, z: 0.00

Vertices Point: x: -6.79, y: 5.29, z: 4.13

Vertices Point: x: -2.93, y: 5.29, z: 4.13

Vertices Point: x: -2.93, y: 5.29, z: 0.00

Vertices Point: x: -6.79, y: 5.29, z: 0.00

Vertices Point: x: -6.79, y: -2.30, z: 0.00

Vertices Point: x: -6.79, y: -2.30, z: 4.13

Vertices Point: x: -6.79, y: 5.29, z: 4.13

Vertices Point: x: -6.79, y: 5.29, z: 0.00

Chunk ID: 0x 4140 Size of Chunk: 264

Number of Vertices 32

Tex Coord: tu: 1.00, tv: 0.00

Tex Coord: tu: 0.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 0.00

Tex Coord: tu: 0.00, tv: 1.00

Tex Coord: tu: 1.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 0.00

Tex Coord: tu: 1.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 1.00

Tex Coord: tu: 0.00, tv: 0.00

Chunk ID: 0x 4160 Size of Chunk: 54

Chunk ID: 0x 4120 Size of Chunk: 202

Number of Faces 12

Face: Index1: 0, Index2: 2, Index3 3

Face: Index1: 3, Index2: 1, Index3 0

Face: Index1: 4, Index2: 5, Index3 7

Face: Index1: 7, Index2: 6, Index3 4

Face: Index1: 8, Index2: 9, Index3 10

Face: Index1: 11, Index2: 12, Index3 13

Face: Index1: 14, Index2: 15, Index3 16

Face: Index1: 17, Index2: 18, Index3 19

Face: Index1: 20, Index2: 21, Index3 22

Face: Index1: 23, Index2: 24, Index3 25

Face: Index1: 26, Index2: 27, Index3 28

Face: Index1: 29, Index2: 30, Index3 31

Chunk ID: 0x 4130 Size of Chunk: 44

8 - Default

Material: FaceCount: 12

FaceAssignedThisMaterial: 0

FaceAssignedThisMaterial: 1

FaceAssignedThisMaterial: 2

FaceAssignedThisMaterial: 3

FaceAssignedThisMaterial: 4

FaceAssignedThisMaterial: 5

FaceAssignedThisMaterial: 6

FaceAssignedThisMaterial: 7

FaceAssignedThisMaterial: 8

FaceAssignedThisMaterial: 9

FaceAssignedThisMaterial: 10

FaceAssignedThisMaterial: 11

Chunk ID: 0x 4150 Size of Chunk: 54

Chunk ID: 0x b000 Size of Chunk: 219

Now to tidy up our code!

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