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Speccy Port

429 bytes added, 12:47, 19 January 2020
/* Graphics with transparency */
=====Graphics with transparency=====
 
======Storage======
A common way to do this is on the Spectrum is to store 1 byte of mask, followed by 1 byte of pixel data, and to repeat this for the width of the sprite divided by 8. (Each byte representing a 8 pixel wide single line slice of the sprite).
Therefore, depending on the representation, this would determine how much ram is consumed on the Amstrad.
The best it seems is to go for mode 1, and use a common mask table, with 3 colours per sprite. The situation is different if you consider tiles, here Here we don't need a mask. For use 256 bytes more than the spectrum a 8x16 tile: (8/8)x16 = 16 bytesSpectrum equivalent graphicsCPC mode 1: (8/4)x16 = 32 bytes CPC mode 0: (4/2)x16 = 32 bytes CPC mode 2: (8/8)x16 = 16 bytes 
So we show that some games could be recoloured and still use about the same amount of data as the Spectrum.
Examples of games where re colouring could have been done:
* [[Pacmania]]
 
=====Graphics without transparency=====
 
======Storage======
 
Tiles are often used to define background graphics. These are opaque and don't need masks. The benefit here is that on CPC we can use all the colours in the palette.
 
However on CPC they will often take more storage space:
 
For the spectrum a 8x16 tile: (8/8)x16 = 16 bytes.
 
CPC mode 0: (4/2)x16 = 32 bytes
 
CPC mode 1: (8/4)x16 = 32 bytes
 
CPC mode 2: (8/8)x16 = 16 bytes
 
In mode 0 and mode 1, the tiles on the CPC will take twice as much space compared to the Spectrum. This will impact the memory used.
=====Real-Time Conversion of Spectrum graphics=====
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