how fast are my blits?

Blitting a 5 bitplane 64x64 rectangle with the cookie cut function (4 active DMA channels) probably isn't going to be very fast.

How fast is it ?

I added a feature to imagecon to generate a greyscale version of the palette.

Then in the main loop I now:

wait for the vertical blank
set the greyscale palette
do 5 blits
set the color palette

.mainLoop:
        bsr.s  waitVerticalBlank
        bsr.s  installGreyscalePalette
        move.l #4,d0 ; blit the object 5 times each frame
.blitLoop:
        bsr.s	 moveBlitterObject
        dbra	 d0,.blitLoop
        bsr.s	 installColorPalette
        bra.s	 .mainLoop

So when the screen changes to color, that's how many scan lines we have used blitting stuff.

The NUM_COLORS variable in the Makefile sets the number of colors. This automatically creates the correct bitplane and palette data as well as reconfiguring the example code. So now we can see what impact the number of bitplanes has on blit speed:

README.md

how fast are my blits?

5 bitplanes

4 bitplanes

3 bitplanes

2 bitplanes

1 bitplanes

try it