Picture Operators

version 6.0

An expression that uses a picture operator returns a picture. The following table shows the picture operators.

The two operators & and | always return a bitmapped picture, no matter what the nature of the two source pictures. The reason is that 4D first draws the pictures into memory bitmaps, then calculates the resulting picture by performing graphical exclusive or inclusive OR on the pixels of the bitmaps.

Note: The COMBINE PICTURES command can be used to superimpose pictures while keeping the characteristics of each source picture in the resulting picture.

The other picture operators return vectorial pictures if the two source pictures are vectorial. Remember, however, that pictures printed by the display format On Background are printed bitmapped.

In the following examples, all of the pictures are shown using the display format On Background.

Here is the picture circle:

Here is the picture rectangle:

In the following examples, each expression is followed by its graphical representation.

• Horizontal concatenation

   circle + rectangle ` Place the rectangle to the right of the circle




   rectangle + circle ` Place the circle to the right of the rectangle

• Vertical concatenation

   circle / rectangle ` Place the rectangle under the circle




   rectangle / circle ` Place the circle under the rectangle

• Exclusive superimposition (XOR)

   circle & rectangle ` Exclusive OR of the two pictures

• Inclusive superimposition (OR)

   circle | rectangle ` Inclusive OR of the two pictures

• Horizontal move

   rectangle + 50 ` Move the rectangle 50 pixels to the right




   rectangle - 50 ` Move the rectangle 50 pixels to the left

• Vertical move

   rectangle /50 ` Move the rectangle down by 50 pixels





   rectangle /-20 ` Move the rectangle up by 20 pixels

• Resize

   rectangle * 1.5 ` The rectangle becomes 50% bigger





   rectangle * 0.5 ` The rectangle becomes 50% smaller

• Horizontal scaling

   circle *+3 ` The circle becomes 3 times wider




   circle *+ 0.25 ` The circle's width becomes a quarter of what it was

• Vertical scaling

   circle */ 2 ` The circle becomes twice as tall




   circle */ 0.25 ` The circle's height becomes a quarter of what it was

Bitwise Operators, COMBINE PICTURES, Comparison Operators, Date Operators, Logical Operators, Numeric Operators, Operators, String Operators, Time Operators, TRANSFORM PICTURE.