1. Sprite Animation
An exercise on filling circles and polygons to create the animated sprite used in ‘Pac Man’

2. What is a ‘sprite’? It’s a small graphics pixmap image
It’s normally stored in off-screen VRAM
It’s ready to be copied to on-screen VRAM
The copying operation is called a ‘BitBlt’
Several sprites can support an animation
Let’s see how to create a sprite array, then synchronize BitBlts with Vertical Retrace

3. The ‘Pac Man’ sprite 1. Fill a circle with the foreground color
2. Fill a triangle in the background color

4. The ‘Pac Man’ sprite-array
Create an array of sprites, arranged in a sequence that
matches the order in which they will be drawn to VRAM

5. Typical animation loop
sprite pacman[ 8 ]; // the array of sprite-images
int i = 0;
while ( !done ) {
draw( pacman[ i ], vramptr );
vsync(); // await next vertical retrace
hide( sprite[ i ], vramptr );
i = ( ++i ) % 8; // cycle through sprite array }

6. Multiple sprite-arrays
RIGHT
DOWN UP

7. Demo: ‘sprites.cpp’ Study the source-code for this demo
Arrange your sprites in an array
Write a sprite-animation loop
Incorporate movement in sprite’s location
Let user control direction with arrow-keys
Store your sprite-arrays in offscreen vram