Writing single pixels to the screen (using GDI graphics) was very fast in Allegro 4 but in Allegro 5 it is very slow - at least as far as I got it to work. So I want to use bitmaps instead.
I have a program that generates a bitmap in TRUECOLOR8888 pixel format in memory and then asks to write this on the screen giving the address and pitch of the bitmap in memory and the position plus width and height where this block of pixels shall be put on the display.
Do I need to lock this bitmap in memory as an Allegro bitmap? Can I define my display where this bitmap shall be written as a bitmap and how do you do that? How do I then copy from the bitmap in memory to the display? The bitmap in memory can start at any position on the screen and end at a different position on another line on the display. I did some reading on this but found no solution.