createCompatableDC what if you don't want a compatible one?

Is it possible to create memory dc's that arn't the same as the current screen setting?

I ask because running my game in 16 bit color rather then 32 bit effectively reduces the memory requirements for the memory dc's by half. However although the sprites look good in 16 bit color the backgrounds do not. The game must run in 32 bit color but is there a way I can create the sprites in 16 bit color and have them still display correctly when windows is running in 32 bit?

I've tryed changing the color settings through vb at the time the dc's get made then changing it back once they are made but that doesn't seem to work as in some cases caused malfunctions.

If your DCs are 16 bit, your images are going to be 16bit, so there is no reason to be running in 32 bit mode while the game is running. You will have 16 bit quality either way.

As for the malfunctions, here is probably the reason:

Code:

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a 32 Bit mode color is:
XXXXXXXX RRRRRRRR GGGGGGGG BBBBBBBB
while a 16 bit mode color is:
RRRRRGGG GGGBBBBB

---

If you notice the above diagrams, 32 bit is, of course, 2 bytes longer. So, when you blit from oen to the other, the 32 bit DC expects 32 bits of color data, while only 16 is provided. The problem is that, for every 2 pixels you get 1 32 bit value, looking something like:

Code:

---

XXXXXXXX GGGBBBBB RRRRRGGG GGGBBBBB

---

Just a bit garbled up, id say =).

This is all conjecture, as I dont know what goes on inside of BitBlt, but it is probable.

Z.

Well it seemed to work for the most part only with occasional problems (although on the whole it seemed to unstable to trust) memory wasn't getting saved like it would if I'd been running in 16 bit for the whole thing. Since I don't need all the quality of a 32-bit color sprite is there no other way to shrink the size of the dc?

Just change the bpp to 16 bits at the beginning of the program, and switching back to whatever bpp the user was running before at the end of the program.

Z.

I wan't to run the game in 32-bit color though because the backgrounds were designed for that and some of them look all blotchy in 16-bit.

ideally I'd want something that would change only the memeory dcs not the rest of the game.

CreateDC, if i remember... you have to give it a bunch of parameters.