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50 lines
2.1 KiB
Markdown
50 lines
2.1 KiB
Markdown
The [_PALETTECOLOR (function)](_PALETTECOLOR-(function)) function is used to return the 32 bit attribute color setting of an image or screen page handle's palette.
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## Syntax
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> color32Value& = [_PALETTECOLOR (function)](_PALETTECOLOR-(function))(attributeNumber%, imgHandle&)
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## Description
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* attributeNumber% is the color attribute value from 0 to 255 for 1, 4 or 8 bit images.
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* imgHandle& is the image handle being read for color data. Zero can be used to read the current screen mode palette.
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* Returns the 32 bit color value to be used by the 32 bit RGB functions.
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* For 32 bit images send the _PALETTECOLOR return value to [_RED32](_RED32), [_GREEN32](_GREEN32) and [_BLUE32](_BLUE32) functions to get the red, green, and blue intensity values.
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* **Although 32 bit palette values are returned, the function cannot be used with 32 bit images or screen modes.**
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## Example(s)
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How _PALETTECOLOR works on 32 bit RGB compared to a 4 BPP(SCREEN 12) QBasic procedure.
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```vb
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SCREEN 12 'can use any QBasic legacy screen mode
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DIM RGB(0 TO 47) AS INTEGER 'color intensity array
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FOR c& = 0 TO 15
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'OUT &H3C7, c& 'set color attribute to read
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value32& = _PALETTECOLOR(c&, 0) 'sets color value to read of an image page handle.
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'red% = INP(&H3C9)
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red% = _RED32(value32&)
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'green% = INP(&H3C9)
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green% = _GREEN32(value32&)
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'blue% = INP(&H3C9)
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blue% = _BLUE32(value32&)
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RGB(c& * 3) = red%: RGB((c& * 3) + 1) = green%: RGB((c& * 3) + 2) = blue%
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NEXT
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FOR i = 0 TO 47 STEP 3
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RGBval$ = LTRIM$(STR$(RGB(i))) + "," + STR$(RGB(i + 1)) + "," + STR$(RGB(i + 2)) + ")"
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PRINT "Color"; i / 3, "_RGB(" + RGBval$;
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PRINT
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NEXT
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END
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```
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> *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 (graphics statement)](GET-(graphics-statement)) the image AFTER the color settings. Just GET the image starting at Array(48).
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## See Also
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* [_PALETTECOLOR](_PALETTECOLOR) (statement)
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* [_NEWIMAGE](_NEWIMAGE), [_LOADIMAGE](_LOADIMAGE)
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* [SAVEIMAGE](SAVEIMAGE) (example code)
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