Palettes - Revision history

Em00k: Removing Sol's lovely corrected image, but we don't need two.

2025-04-08T14:25:15Z

Removing Sol's lovely corrected image, but we don't need two.

← Older revision		Revision as of 15:25, 8 April 2025
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	<code>res = src × 255 ÷ 7</code>		<code>res = src × 255 ÷ 7</code>

	~~[[File:256-palette-2.png\|thumb\|left\|Alternate 8-bit RGB values]]~~
	<br clear="all">		<br clear="all">

Em00k: Added Tilemap

2025-04-07T18:03:12Z

Added Tilemap

← Older revision		Revision as of 19:03, 7 April 2025
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	** <code>010</code> = Sprites 1st		** <code>010</code> = Sprites 1st
	** <code>110</code> = Sprites 2nd		** <code>110</code> = Sprites 2nd
			** <code>011</code> = Tilemap 1st
			** <code>111</code> = Tilemap 2nd
	* bit 3 = Use Sprites palette (0 = first palette, 1 = second palette) (soft reset = 0)		* bit 3 = Use Sprites palette (0 = first palette, 1 = second palette) (soft reset = 0)
	* bit 2 = Use Layer 2 palette (0 = first palette, 1 = second palette) (soft reset = 0)		* bit 2 = Use Layer 2 palette (0 = first palette, 1 = second palette) (soft reset = 0)

Em00k: /* {{NextRegNo|$44}} – 9-bit Colour Value */

2025-04-07T18:00:59Z

{{NextRegNo|$44}} – 9-bit Colour Value

← Older revision		Revision as of 19:00, 7 April 2025
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	*** bit 0 = third blue bit		*** bit 0 = third blue bit
	*** For Layer 2: bit 7 = '''priority colour''' (Layer 2 pixel is drawn above all other layers). If you need the same colour in both priority and normal modes, you will need to have two different entries with the same colour one with and one without priority.		*** For Layer 2: bit 7 = '''priority colour''' (Layer 2 pixel is drawn above all other layers). If you need the same colour in both priority and normal modes, you will need to have two different entries with the same colour one with and one without priority.
	* Auto-increments index if ~~enabled~~ in {{NextRegNo\|$43}}		* Auto-increments index if bit 7 is 0 in {{NextRegNo\|$43}}
	* Reads only return second byte - does not increment.		* Reads only return second byte - does not increment.
	* Writing to {{NextRegNo\|$40}}, {{NextRegNo\|$41}}, or {{NextRegNo\|$43}} resets to first write		* Writing to {{NextRegNo\|$40}}, {{NextRegNo\|$41}}, or {{NextRegNo\|$43}} resets to first write

Em00k: Fixed paste error

2025-04-07T17:49:58Z

Fixed paste error

← Older revision		Revision as of 18:49, 7 April 2025
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	To increase the number of available colours on screen, the Spectrum Next supports '''palletized colours'''. The number of displayable colours varies depending on the graphics mode:		To increase the number of available colours on screen, the Spectrum Next supports '''palletized colours'''. The number of displayable colours varies depending on the graphics mode:

	* '''ULA''' – 16 colours on screen at once (8 with optional BRIGHT) , using 1 of 2 ~~sprite~~ palettes		* '''ULA''' – 15 colours on screen at once (7 with optional BRIGHT - as bright black is still black), using 1 of 2 ULA palettes
	* '''ULANext''' – Up to 256 colours via attribute mapping, using 1 of 2 ~~sprite~~ palettes		* '''ULANext''' – Up to 256 colours via attribute mapping, using 1 of 2 ULA Next palettes
	* '''Sprites''' – 16 colours per sprite (4-bit) with palette offsets or 256 colours (8-bit), using 1 of 2 sprite palettes		* '''Sprites''' – 16 colours per sprite (4-bit) with palette offsets or 256 colours (8-bit), using 1 of 2 sprite palettes
	* '''Layer 2''' – Full 256-colour display, using 8-bit pixel values as palette indices, using 1 of 2 Layer2 palettes		* '''Layer 2''' – Full 256-colour display, using 8-bit pixel values as palette indices, using 1 of 2 Layer2 palettes
	* '''Tilemap''' – ~~Each tile can select one~~ of two tilemap palettes~~; each pixel index maps to a~~ colour ~~within that palette~~		* '''Tilemap''' – One of two tilemap palettes used for final colour lookup.

	Colour IDs in [[Layer 2]], [[Sprites]], and the [[ULA]] are treated as '''palette indices'''. These indices point to colours defined in the palette memory.		Colour IDs in [[Layer 2]], [[Sprites]], and the [[ULA]] are treated as '''palette indices'''. These indices point to colours defined in the palette memory.

Em00k: /* Palettes and Colour Mapping */

2025-04-07T17:45:42Z

Palettes and Colour Mapping

← Older revision		Revision as of 18:45, 7 April 2025
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	* '''ULANext''' – Up to 256 colours via attribute mapping, using 1 of 2 sprite palettes		* '''ULANext''' – Up to 256 colours via attribute mapping, using 1 of 2 sprite palettes
	* '''Sprites''' – 16 colours per sprite (4-bit) with palette offsets or 256 colours (8-bit), using 1 of 2 sprite palettes		* '''Sprites''' – 16 colours per sprite (4-bit) with palette offsets or 256 colours (8-bit), using 1 of 2 sprite palettes
	* '''Layer 2''' – Full 256-colour display, using 8-bit pixel values as palette indices, using 1 of 2 ~~sprite~~ palettes		* '''Layer 2''' – Full 256-colour display, using 8-bit pixel values as palette indices, using 1 of 2 Layer2 palettes
	* '''Tilemap''' – Each tile can select one of two tilemap palettes; each pixel index maps to a colour within that palette		* '''Tilemap''' – Each tile can select one of two tilemap palettes; each pixel index maps to a colour within that palette

Em00k at 19:51, 5 April 2025

2025-04-05T19:51:53Z

Show changes

Em00k at 18:19, 5 April 2025

2025-04-05T18:19:05Z

← Older revision		Revision as of 19:19, 5 April 2025
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	[[File:256-palette.png\|left\|thumb\| Default 256 colour 8-bit indexed palette.]]		[[File:256-palette-2.png\|left\|thumb\| Default 256 colour 8-bit indexed palette.]]
	<br clear=all>		<br clear=all>

Sol HSA: added alternative rgb values

2025-03-15T14:10:59Z

added alternative rgb values

← Older revision		Revision as of 15:10, 15 March 2025
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	[[File:256-palette.png\|left\|thumb\| Default 256 colour 8-bit indexed palette.]]		[[File:256-palette.png\|left\|thumb\| Default 256 colour 8-bit indexed palette.]]
			<br clear=all>

			Since next has 3 bit color and modern computers have 8 bit, conversion between the two always leads to either inventing or discarding information. Here's an alternative 8-bit palette that is calculated by scaling the 3 bit (0..7) values to 8 bit (0..255) linearly (res=src*255/7):

			[[File:256-palette-2.png\|thumb\|left\|Alternate 8 bit rgb values]]

Em00k at 18:30, 31 October 2024

2024-10-31T18:30:09Z

← Older revision		Revision as of 19:30, 31 October 2024
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	[[File:256-palette.png\|Default 256 colour palette. ]]		[[File:256-palette.png\|left\|thumb\| Default 256 colour 8-bit indexed palette.]]

Em00k at 01:02, 31 October 2024

2024-10-31T01:02:14Z

← Older revision		Revision as of 02:02, 31 October 2024
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	[[File:256-palette.png~~\|thumb\|left~~\|Default 256 colour palette. ]]		[[File:256-palette.png\|Default 256 colour palette. ]]