Ball

Definition

A round ‘sprite’ that can be placed on a Canvas, where it can react to touches and drags, interact with other sprites (ImageSprites and other Balls) and the edge of the Canvas, and move according to its property values.

For example, to have a Ball move 4 pixels toward the top of a Canvas every 500 milliseconds (half second), you would set the Speed property to 4 [pixels], the Interval property to 500 [milliseconds], the Heading property to 90 [degrees], and the Enabled property to true. These and its other properties can be changed at any time.

The difference between a Ball and an ImageSprite is that the latter can get its appearance from an image file, while a Ball’s appearance can only be changed by varying its PaintColor and Radius properties.

Properties

Enabled

Controls whether the Ball moves when its speed is non-zero.

Heading

The Ball’s heading in degrees above the positive x-axis. Zero degrees is toward the right of the screen; 90 degrees is toward the top of the screen.

Interval

The interval in milliseconds at which the Ball’s position is updated. For example, if the Interval is 50 and the Speed is 10, then the Ball will move 10 pixels every 50 milliseconds.

OriginAtCenter

Whether the x- and y-coordinates should represent the center of the Ball (true) or its left and top edges (false).

PaintColor

The color of the Ball.

Radius

The distance from the center of the Ball to its edge.

Speed

The speed at which the Ball moves. The Ball moves this many pixels every Interval milliseconds if Enabled is true.

Visible

Sets whether sprite should be visible.

X

The horizontal coordinate of the Ball, increasing as the Ball moves right. If the property OriginAtCenter is true, the coordinate is for the center of the Ball; otherwise, it is for the leftmost point of the Ball.

Y

The vertical coordinate of the Ball, increasing as the Ball moves down. If the property OriginAtCenter is true, the coordinate is for the center of the Ball otherwise, it is for the uppermost point of the Ball.

Z

How the Ball should be layered relative to other Balls and ImageSprites, with higher-numbered layers in front of lower-numbered layers.