> > How many simultaneous colors can the SAM display > > in what graphic modes (the FAQ is not very > > explicit save the 512x192 mode)? Can all 128 > > be used? > > Yep, if you use line interrupts but this is not practical for images, > the best I have seen is 32 colours in Mode 4 that still looks alright. > > Has anbody got a converter that can take a 32/256 BMP and do this?
Nope... btw, for clarity, Mode 4 displays 16 colours, in a chunky pel format -- eg each byte holds: CL3|CL2|CL1|CL0||CL3|CL2|CL1|CL0 -- || marks boundary for two adjacent pixels Each byte holds 2 pixels, one in each nybble, the left hand pixel is in the upper nybble, right hand pixel in the lower nybble. The 4 bits form an offset into the 16 position Colour Look Up Table, giving 16 colours in mode 4. The colour look up table entries are made up as such: xx|GREEN1|RED1|BLUE1|INTENSITY|GREEN0|RED0|BLUE0 xx = don't care. The intensity bit has half the value of the RED0 GREEN0 and BLUE0 bits, but is applied to all. Going off the ST style of doing things, think of GREEN1,RED1 and BLUE1 being worth 4 intensity units, GREEN0, RED0 and BLUE0 being worth 2 intensity units, and INTENSITY being worth 1, but on all channels... > > If so, what is the bit plane arrangement? > > How many levels per channel (RGB)? With 128 > > colors, something must be weird. If every channel > > can have the same number of levels then the total > > number of colors should be the number of levels > > cubed (i.e. 8 levels per channel would be > > 8 red x 8 green x 8 blue = 512 colors, like on an > > Atari ST). > > I know that the Sam palette is weird and has 128 colours and that's > as far as me and the palette go, any enlightenment from others? See above ;) Simon
