Bitmap and Vector Graphics
 
Below are examples of a bitmap image and a vector image.
 
Bitmap (Raster)
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Vector
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Bitmaps are sometimes called "continuous color" images. This refers to the
gradual color changes across the image, allowing for smooth changes of color and
non-sharp edges. This is accomplished by using multiple shades of the same color.
The bitmap image above has 10,428 different colors while the vector image uses 9.
 
 
Bitmap Images
 
Bitmap images are a created from a grid of small dots called pixels.
 
Normal size
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400% zoom
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Vector Images
 
Vector graphics store image information mathematically as lines, circles, and arcs.
For this reason vector graphics are sometimes called object graphics. As an example
take a look at the first line in the sample code.
 
Circle (15,15) r 15
This would translate as a circle object with a center at X=15,Y=15 and a radius of 15.
 
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Circle (15,15) R=15
Polygon (15,15) R=15 Sides=6 Inscribed
Triangle (15,15) (22.7,21.3) (26.2,21.5)
Triangle (15,15) (26.2,21.5) (24.3,18.5)
Ellipse (17.7,10.3) A=1.9 B=0.7
Arc (11.2,18.1) (11.5,21.0) (14.2,19.9)
Arc (11.2,18.1) (10.8,22.2) (14.2,19.9)
|
 
 
Resolution and Scaling
 
While vector images do not allow for smooth color transitions they do
allow for the image to be scaled up or down with no loss in quality unlike
bitmaps. The following two images have been scaled up by 400%.
The bottom left hand corner has been cropped out and is shown below.
 
 
This clearly shows one the benefits of vector images, scalability. Since vector images
are defined mathematically, the image can be sized up or down with no loss in quality.
Bitmaps on the other hand, have to interpolate the colors between pixels when scaling
 
 
Next ----->
3. Bitmaps In Detail