Colour mouse cursors

SDL Development
1

Hiya,

are there any plans to support colour mouse cursors at some stage?--

-dv

2

If you’d like to have a color cursor now, just hide the mouse and draw
your own, then it can be in color, animated, translucent, or whatever
else you would like to do with it, and completely platform independent
too.

Phoenix Kokido
members.xoom.com/kokido
@Wes_Poole

Daniel wrote:> Hiya,

are there any plans to support colour mouse cursors at some stage?

–

-dv

3

Hiya,

are there any plans to support colour mouse cursors at some stage?

There was once color cursor support in SDL, but it was removed because
flickerless color cursor blitting really needs to be handled by the app.
Only the app knows exactly which pixels are changing when a blit is done.

The general format of color cursor mixing:

Blit:
Draw the area behind the cursor (removing it)
Perform the blit
Save the area behind the cursor (for next time)
Redraw the cursor on the screen
Update the rectangle

This causes flicker when writing directly to video memory.
There is a technique that can be used to do flickerless
mouse drawing, but it is fairly complicated and involves
rectangle intersection and lots of offscreen work buffers.

See ya!
-Sam Lantinga (slouken at devolution.com)

Lead Programmer, Loki Entertainment Software–
“Any sufficiently advanced bug is indistinguishable from a feature”
– Rich Kulawiec

4

I can post a demo of a user created mouse cursor to this list if
anyone is interested.

Phoenix Kokido
members.xoom.com/kokido
@Wes_Poole

Sam Lantinga wrote:> > Hiya,

are there any plans to support colour mouse cursors at some stage?

There was once color cursor support in SDL, but it was removed because
flickerless color cursor blitting really needs to be handled by the app.
Only the app knows exactly which pixels are changing when a blit is done.

The general format of color cursor mixing:

Blit:
Draw the area behind the cursor (removing it)
Perform the blit
Save the area behind the cursor (for next time)
Redraw the cursor on the screen
Update the rectangle

This causes flicker when writing directly to video memory.
There is a technique that can be used to do flickerless
mouse drawing, but it is fairly complicated and involves
rectangle intersection and lots of offscreen work buffers.

See ya!
-Sam Lantinga (slouken at devolution.com)

Lead Programmer, Loki Entertainment Software

“Any sufficiently advanced bug is indistinguishable from a feature”
– Rich Kulawiec

5

In Message <19991203173600.10250.qmail at venus.postmark.net>
Phoenix Kokido wrote:

I can post a demo of a user created mouse cursor to this list if
anyone is interested.

Yes, do it please, I am very interested. Or send it directly to my
E-mail if you think it is too big for the list.

Sam Lantinga wrote:

There is a technique that can be used to do flickerless
mouse drawing, but it is fairly complicated and involves
rectangle intersection and lots of offscreen work buffers.

Where can I learn more about this technique? Is there any literature or
web ressources or source code available?–
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