Hands On DarkBASIC Pro - Digital Skills

LISTING-32.1
Adding Texture to an
Object
Mipmaps
For example, we could apply image 1 to object 2 using the line
TEXTURE OBJECT 2,1
The program in LISTING-32.1 demonstrates how a cube can be textured with a
wood image to create the impression of a wooden crate.
REM *** Set display resolution ***
SET DISPLAY MODE 1280,1024,32
REM *** Load texture image ***
LOAD IMAGE "textureWood.jpg",1
REM *** Create cube ***
MAKE OBJECT CUBE 1,40
REM *** Add texture to cube ***
TEXTURE OBJECT 1,1
REM *** Position cube ***
POSITION OBJECT 1,25,0,100
REM *** Rotate cube continuously ***
DO
TURN OBJECT LEFT 1, 1.0
LOOP
REM *** End program ***
END
Activity 32.1
Type in and test the program in LISTING-32.1 (texture01.dbpro).
Change the texture image to eyecol.bmp.
We can see quite clearly from the results of the last Activity that the image is applied
separately to each face of the cube. For other shapes, the image may be applied
differently.
Activity 32.2
Modify your last program so that eyecol.bmp is applied as a texture to a box,
cylinder, cone and sphere (any dimensions will do). Create a separate program
for each shape.
How often is the image repeated on each of the shapes?
Texturing a 3D object can be quite time consuming. It may be easy enough to map
a 300 by 300 pixel image onto a flat surface which occupies exactly 300 by 300
pixels on the screen, but if the 3D object moves off into the distance, the computer
has to work much harder to map the same 300 by 300 image onto an object which
now occupies just 23 by 23 pixels on the screen.
To help with this problem DarkBASIC Pro creates more than one copy of any image
that is loaded, with each copy being exactly half the size of the last (see FIG-32.3).
DarkBASIC Pro: Texturing 799