Object File
Format (.q3o)
A quick3D object file consists of a header and one to three chunks.
The three possible types of chunks are the mesh definitions chunk,
the material definitions chunk, and the texture definitions chunk.
They are binary files and will always have at least a header and a
meshes chunk, but may not have materials or textures chunks. The
file format uses the following data types:
char = 1 byte
bool = 1 byte (0=FALSE or 1=TRUE)
short = 2 bytes
int = 4 bytes
long = 4 bytes
float = 4 bytes
vertex = 12 bytes (three float's)
normal = 12 bytes (three float's)
texUV = 8 bytes (two float's)
pixel = 3 bytes (three unsigned char's)
face = (4 * X) bytes (X int's)
string = length of string bytes (including the '\0')
color = 12 bytes (three float's)
matrix = 64 bytes (16 float's)
X represents the "shape" of the face, or in other words, the number
of vertices involved in the particular face.
The header starts the file and has the following 22-byte
structure:
HEADER {
char signature[8];
char version[2];
int numberMeshes;
int numberMaterials;
int numberTextures;
}
The signature field always contains "quick3Do" and identifies the
file as a quick3D Object file. The next two char's contain the
version of the quick3D file format used in the file. The current
version is "30". Then follows three int's, the first being the
number of meshes in the mesh definitions section, next the number
of materials in the materials chunk, and finally the number of
textures in the textures chunk. In the case where there are no
materials and/or no textures, the number will be 0.
Each of the three chunk types also have their own single-byte
header:
CHUNK_HEADER {
char type;
}
The type will be one of 'm', 'c', or 't', signaling a meshes chunk,
materials chunk, or textures chunk respectively.
The mesh definitions chunk contains numberMeshes(contained in the
file header) mesh definitions following its 1-byte chunk header.
The mesh definitions come one after the other and each definition
has the following structure:
MESH {
long numberVertices;
vertex vertices[numberVertices];
long numberFaces;
short faceShapes[numberFaces];
face faces[numberFaces]
int materialIndices[numberFaces];
long numberNormals;
normal normals[numberNormals];
long numberTextureCoordinates;
texUV textureCoordinates[numberTextureCoordinates];
face textureIndices[numberFaces];
vertex centerOfMass;
float boundingBox[6];
}
If numberTextures from the file header is zero, then there will be
no textureCoordinates nor textureIndices.
The materials definitions chunk contains numberMaterials(contained
in the file header) material definitions following its 1-byte chunk
header. The material definitions come one after the other and each
definition has the following structure:
MATERIAL {
string materialName;
color ambientColor;
color diffuseColor;
color specularColor;
float transparency;
}
The texture definitions chunk contains numberTextures(contained in
the file header) texture definitions following its 1-byte chunk
header. The texture definitions come one after the other and each
definition has the following structure:
TEXTURE {
string textureName;
int textureWidth;
int textureHeight;
pixel texture[textureWidth * textureHeight]
}
Scene File Format (.q3s)
The quick3D scene file is almost identical to the object format
except that there is a different value in the signature field, and
there is one additional chunk. The additional chunk is the scene
chunk and contains data related to a quick3D scene. These are also
binary files and will always have at least a header and a scene
chunk, but may not have meshes, materials, or textures chunks. The
scene file format uses the same data types as the object
format.
The header starts the file and has the following 22-byte
structure:
HEADER {
char signature[8];
char version[2];
int numberMeshes;
int numberMaterials;
int numberTextures;
}
The signature field always contains "quick3Ds" and identifies the
file as a quick3D Scene file. The next two char's contain the
version of quick3D that wrote the file. The current version is
"30". Then follows three int's, the first being the number of
meshes in the mesh definitions section, next the number of
materials in the materials chunk, and finally the number of
textures in the textures chunk. In the case where there are no
meshes, materials, and/or no textures, the number will be 0.
Each of the four chunk types also have their own header of the
following 1-byte structure (this is just like an object file):
CHUNK_HEADER {
char type;
}
The type will be one of 'm', 'c', 't', or 's', signaling a meshes
chunk, materials chunk, textures chunk, or scene chunk
respectively
The mesh, material, and texture definitions chunks in a scene file
are exactly the same as in an object file. The scene chunk has the
following structure:
SCENE {
float position[3];
matrix transformation;
float axis[3];
float angle;
float eyePosition[3];
float eyeRotation[3];
color foregroundColor;
color backgroundColor;
bool usingEyeFilter;
color eyeFilterColor;
float eyeFilterAmount;
color lightColor;
int backgroundImageWidth;
int backgroundImageHeight;
string backgroundFilename;
pixel backgroundImage[bgWidth * bgHeight];
float depthCuing;
color depthCueColor;
float gamma;
}
The position is the x, y, z in world space. The axis is the vector
about which the model is rotated angle degrees about. This is also
stored in matrix form in transformation. The eye point's
orientation is represented by eyePosition and eyeRotation. Next are
the foregroundColor and backgroundColor. Note that any materials
specified in the mesh will override the foreground color.
usingEyeFilter tells whether an eye filter is in use. The
eyeFilterColor is the color of the eye filter, and eyeFilterAmount
is its strength (if not used these may be all zero). The color of
the light in the scene is stored in lightColor. If there is a
background image, backgroundImageWidth and backgroundImageHeight
will specify the image dimentions and backgroundImage will specify
the pixel data. If backgroundImageWidth and backgroundImageHeight
both equal zero, then there is no backgroundImage(the
backgroundColor is used). Next, depthCuing specifies the amount of
"depth" to be added to the scene (in the range of least to most,
0.0 - 1.0). The depthCueColor is next. The final part of the scene
chunk is the gamma value used in the scene. |
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