PALETTECOLOR (function): Difference between revisions
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{{PageExamples}} | {{PageExamples}} | ||
''Example:'' How _PALETTECOLOR works on 32 bit RGB compared to a 4 BPP(SCREEN 12) QBasic procedure. | ''Example:'' How _PALETTECOLOR works on 32 bit RGB compared to a 4 BPP(SCREEN 12) QBasic procedure. | ||
{{CodeStart}} | {{CodeStart}} | ||
SCREEN 12 'can use any QBasic legacy screen mode | SCREEN 12 'can use any QBasic legacy screen mode | ||
DIM RGB(0 TO 47) AS INTEGER 'color intensity array | DIM RGB(0 TO 47) AS INTEGER 'color intensity array | ||
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PRINT | PRINT | ||
NEXT | NEXT | ||
END | END | ||
{{CodeEnd}} | {{CodeEnd}} | ||
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{{PageSeeAlso}} | {{PageSeeAlso}} | ||
* [[_PALETTECOLOR]] | * [[_PALETTECOLOR]] | ||
* [[_NEWIMAGE]], [[_LOADIMAGE]] | * [[_NEWIMAGE]], [[_LOADIMAGE]] | ||
* [[ | * [[SaveImage SUB]] | ||
{{PageNavigation}} | {{PageNavigation}} | ||
Latest revision as of 20:03, 5 January 2024
The _PALETTECOLOR function is used to return the 32 bit attribute color setting of an image or screen page handle's palette.
Syntax
- color32Value& = _PALETTECOLOR(attributeNumber%, imgHandle&)
Description
- attributeNumber% is the color attribute value from 0 to 255 for 1, 4 or 8 bit images.
- imgHandle& is the image handle being read for color data. Zero can be used to read the current screen mode palette.
- Returns the 32 bit color value to be used by the 32 bit RGB functions.
- For 32 bit images send the _PALETTECOLOR return value to _RED32, _GREEN32 and _BLUE32 functions to get the red, green, and blue intensity values.
- Although 32 bit palette values are returned, the function cannot be used with 32 bit images or screen modes.
Examples
Example: How _PALETTECOLOR works on 32 bit RGB compared to a 4 BPP(SCREEN 12) QBasic procedure.
SCREEN 12 'can use any QBasic legacy screen mode DIM RGB(0 TO 47) AS INTEGER 'color intensity array FOR c& = 0 TO 15 'OUT &H3C7, c& 'set color attribute to read value32& = _PALETTECOLOR(c&, 0) 'sets color value to read of an image page handle. 'red% = INP(&H3C9) red% = _RED32(value32&) 'green% = INP(&H3C9) green% = _GREEN32(value32&) 'blue% = INP(&H3C9) blue% = _BLUE32(value32&) RGB(c& * 3) = red%: RGB((c& * 3) + 1) = green%: RGB((c& * 3) + 2) = blue% NEXT FOR i = 0 TO 47 STEP 3 RGBval$ = LTRIM$(STR$(RGB(i))) + "," + STR$(RGB(i + 1)) + "," + STR$(RGB(i + 2)) + ")" PRINT "Color"; i / 3, "_RGB(" + RGBval$; PRINT NEXT END |
- Explanation: To save a bitmap or other image you need the RGB color settings or the colors will look all wrong. You can store that information into a larger image array and GET the image AFTER the color settings. Just GET the image starting at Array(48).
See also