PSet
Plots a single pixel
PSet [target ,] [STEP] (x, y) [,color]
target
target specifies buffer to draw on. target may be an image created with ImageCreate or Get (Graphics). If omitted, target defaults to the screen's current work page.
(x, y) are the coordinates of the pixel. STEP if present, indicates that (x, y) coordinates are relative to the graphics cursor position. If omitted, (x, y) are relative to the upper left-hand corner of target. The x and y coordinates are affected by the last call to the View (Graphics) and Window statements, and respect the current clipping region as set by the View (Graphics) statement.
color specifies the color attribute, as an 8-bit palette index in 8 bpp indexed modes, a 24-bit RGB value in 16 bpp modes (upper 8 bits of the integer unused, limited precision of R,G,B), and a 32-bit RGB or RGBA value in 32 bpp modes (upper 8 bits unused or holding Alpha). Note that it does NOT accept a 16-bit value (5 bits R + 6 bits G + 5 bits B). If omitted, color defaults to the current foreground color.
Speed note: while PSet provides valid results, it is quite slow to call repeatedly due to the overhead of additional calculations and checks. Much better performance can be achieved by using direct memory access using the results obtained from ImageInfo and ScreenInfo/ScreenPtr.
Syntax
PSet [target ,] [STEP] (x, y) [,color]
Parameters
target
specifies buffer to draw on.
STEPindicates that coordinates are relative
(x, y)coordinates of the pixel.
colorthe color attribute.
Description
target specifies buffer to draw on. target may be an image created with ImageCreate or Get (Graphics). If omitted, target defaults to the screen's current work page.
(x, y) are the coordinates of the pixel. STEP if present, indicates that (x, y) coordinates are relative to the graphics cursor position. If omitted, (x, y) are relative to the upper left-hand corner of target. The x and y coordinates are affected by the last call to the View (Graphics) and Window statements, and respect the current clipping region as set by the View (Graphics) statement.
color specifies the color attribute, as an 8-bit palette index in 8 bpp indexed modes, a 24-bit RGB value in 16 bpp modes (upper 8 bits of the integer unused, limited precision of R,G,B), and a 32-bit RGB or RGBA value in 32 bpp modes (upper 8 bits unused or holding Alpha). Note that it does NOT accept a 16-bit value (5 bits R + 6 bits G + 5 bits B). If omitted, color defaults to the current foreground color.
Speed note: while PSet provides valid results, it is quite slow to call repeatedly due to the overhead of additional calculations and checks. Much better performance can be achieved by using direct memory access using the results obtained from ImageInfo and ScreenInfo/ScreenPtr.
Example
' Set an appropriate screen mode - 320 x 240 x 8bpp indexed color
ScreenRes 320, 240, 8
' Plot a pixel at the coordinates 100, 100, Color 15. (white)
PSet (100, 100), 15
' Confirm the operation.
Locate 1: Print "Pixel plotted at 100, 100"
' Wait for a keypress.
Sleep
' Plot another pixel at the coordinates 150, 150, Color 4. (red)
PSet (150, 150), 4
' Confirm the operation.
Locate 1: Print "Pixel plotted at 150, 150"
' Wait for a keypress.
Sleep
' Plot a third pixel relative to the second, Color 15. (white)
' This pixel is given the coordinates 60, 60. It will be placed
' at 60, 60 plus the previous coordinates (150, 150), thus plotting at 210, 210.
PSet Step (60, 60), 15
' Confirm the operation.
Locate 1: Print "Pixel plotted at 150 + 60, 150 + 60"
' Wait for a keypress
Sleep
' Explicit end of program
End
ScreenRes 320, 240, 8
' Plot a pixel at the coordinates 100, 100, Color 15. (white)
PSet (100, 100), 15
' Confirm the operation.
Locate 1: Print "Pixel plotted at 100, 100"
' Wait for a keypress.
Sleep
' Plot another pixel at the coordinates 150, 150, Color 4. (red)
PSet (150, 150), 4
' Confirm the operation.
Locate 1: Print "Pixel plotted at 150, 150"
' Wait for a keypress.
Sleep
' Plot a third pixel relative to the second, Color 15. (white)
' This pixel is given the coordinates 60, 60. It will be placed
' at 60, 60 plus the previous coordinates (150, 150), thus plotting at 210, 210.
PSet Step (60, 60), 15
' Confirm the operation.
Locate 1: Print "Pixel plotted at 150 + 60, 150 + 60"
' Wait for a keypress
Sleep
' Explicit end of program
End
Differences from QB
- target is new to FreeBASIC
- In 16 bpp and 32 bpp modes, a 32-bit value is required instead of an 8-bit palette index
See also