Moving 3D Objects
This section covers how to move models and polygons.
Moving Models
When continuously moving a model (e.g. for animation), it is generally best to use coordinate systems, which will be discussed later.
However, if you simply want to move a model once or only a few times, you can use the moveModel function for a simpler approach.
- Function Format -
int modelID,
float dx, float dy, float dz
)
Arguments:
- modelID: Specifies the ID of the model to move.
- dx, dy, dz: Specify the distance to move in the X, Y, and Z directions respectively.
This function moves the model by modifying the coordinate values of all polygons that make up the model.
As a result, this method is slightly more computationally expensive than coordinate system-based movement (discussed later). It also only allows additive movement, which can be inconvenient if you need to reset the model to its original position. That said, it's convenient for one-time or infrequent movements where these limitations are not an issue.
Moving Individual Polygons
To move a single polygon (rather than a model), use the movePolygon function.
- Function Format -
int polygonID,
float dx, float dy, float dz
)
Arguments:
- Specifies the ID of the polygon to move.
- Specify the distance to move in the X, Y, and Z directions respectively.
Example Program
Basic Example: Moving an Object Once
Let's try placing a sphere model and moving it along the Z-axis. Write and run the following code:
When you run this program, a white sphere will appear on a black background. The sphere will have been moved 2 units in the Z direction.
import graphics3d.Graphics3DFramework;
import Graphics3D;
// This function is called at the start of the program
void onStart ( int rendererID ) {
// Set window size and background color (optional)
setWindowSize( 800, 600 );
setBackgroundColor( 0, 0, 0, 255 );
// Generate and mount axis model
int axis = newAxisModel( 3.0, 3.0, 3.0 );
mountModel( axis, rendererID );
// Generate and mount sphere model
int sphere = newSphereModel( 1.0, 1.0, 1.0, 10, 7 );
mountModel( sphere, rendererID );
// Move along the Z-axis
moveModel( sphere, 0.0, 0.0, 2.0 );
}
Move.vcssl
When you run this program, a white sphere will appear on a black background. The sphere will have been moved 2 units in the Z direction.

Animation Example: Moving Gradually
To move a model in an animation-like fashion, incrementally move it in the onUpdate function. This function is automatically called several dozen times per second by the framework.
import graphics3d.Graphics3DFramework;
import Graphics3D;
// Variables to store model IDs
int axis, sphere;
// Called at the start of the program
void onStart ( int rendererID ) {
// Set window size and background color (optional)
setWindowSize( 800, 600 );
setBackgroundColor( 0, 0, 0, 255 );
// Generate and mount axis model
axis = newAxisModel( 3.0, 3.0, 3.0 );
mountModel( axis, rendererID );
// Generate and mount sphere model
sphere = newSphereModel( 1.0, 1.0, 1.0, 10, 7 );
mountModel( sphere, rendererID );
}
// Called several dozen times per second
void onUpdate (int renderer) {
// Move gradually along the X-axis
moveModel( sphere, 0.02, 0.0, 0.0 );
}
MoveAnimation.vcssl
When you run this program, the white sphere will slowly move along the X-axis in an animated manner.

- 3D Computer Graphics
- Setting Up the Foundation
- Mouse Control and Animation
- Using the Framework
- Creating and Placing Light Sources (and Adjusting Their Properties)
- Creating and Placing Models / Standard Models
- Creating and Placing Polygons, and Various Types of Polygons
- Moving 3D Objects
- Rotating 3D Objects
- Scaling 3D Objects
- Flipping 3D Objects
- Setting Colors for 3D Objects
- Configuring the Shape of 3D Objects
- Fill Settings for 3D Objects
- Material Settings for 3D Objects
- Understanding Coordinate Systems: Concepts, Creation, and Placement
- Moving Coordinate Systems
- Walking Coordinate Systems
- Controlling the Origin Position of a Coordinate System
- Rotating Coordinate Systems
- Spinning a Coordinate System
- Euler Angle-Based Attitude Control of Coordinate Systems
- Camera Work
- Creating, Placing, and Performing Basic Operations on Vectors
- Coordinate Transformations
- Screen Projection
- Collision Detection