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#HELP with ColorMaps

16 messages in this thread

#42081From: Michael WilliamsAug 3, 1994 4:37 PM

HELP!! I am trying to open a 256 color screen, on an AMIGA 4000 running 39.29 I don't understand the new ColorMap scheme at all! Although the type of the screen's ColorMap is 02 the Map is still 4 bits per gun! Therefore I cannot use the new SetRGB32CM (and the like) functions. Does anybody know where I can find some information on this subject? Does anybody have any sample code that might help me? Thank You, MW

#42088From: Steve AhlstromAug 4, 1994 2:51 PM

Can you elaborate a bit or show some code you've tried? I don't understand the problem. Opening a 256 color screen is fairly trivial. -sja

#42089From: Michael WilliamsAug 4, 1994 3:43 PM

I think I figured it out. My problem was that I was trying to look at the structure in ViewPort.ColorMap->ColorTable and expected it to contain colors at 8 bits per gun. I also was using SetRGB32 (vp, 0L, 127L, 127L, 127L); instead of SetRGB32 (vp, 0L, 127L << 24, 127L << 24, 127L << 24); I found some sample code that used the upper 8 bits, and it seems to work. Where can I find some documentation on the new functions and structures in V39.0? I am getting tired of looking through the include files and trying to figure it out? Appreciate the help, Mike Williams

#42090From: Steve AhlstromAug 4, 1994 4:23 PM

Michael, The only doc that exists would be the AutoDocs from CATS. If you are a registered developer (or were before the bankruptcy was declared) you can get the AutoDoc from the developer section on BIX. If not, you'll probably just have to look at other people's source and try to figure the stuff out.

#42093From: Michael WilliamsAug 4, 1994 11:40 PM

This does not sound very encouraging! I was not a registered developer! Thank you for the help though! MW

#42126From: Wolf FaustAug 7, 1994 12:32 PM

You can get docs about the colormap from the AutoDocs and examples in AmigaMail. I personaly found AmigaMail more informativ on this case. However, you don't have to be developer to get the info. For instance, you can get the native developer kit even without being a developer from CATS (at least in Europe Hirsch&Wolf does offer/ship it). However, you can not get the latest 3.1 info without being developer. But, accessing colormap's directly should be avoided under any circumstances as colormaps might change (as you allready found out yourself). Use the SetRGB and GetRGB functions! Another note: in your example you simply shift by 24. However, some hardware/software might make also use of the lower bits. That's why AutoDocs recommend ORing values. So instead of 127<<24 use (val<<24)|(val<<16)|(val<<8)|(val) with val == 127 in your case. Ok? — Wolf Faust, Am Dorfgarten 10, 60435 Frankfurt, Germany —

#42131From: Werner KazmierzakAug 7, 1994 4:58 PM

>> You can get docs about the colormap from the AutoDocs and examples in >> AmigaMail. Wolf, PMFJI, but what issue/page of AmigaMail are those AutoDocs/Examples about colormaps ? I can't allocate anything in the table of centents. BTW, the last issue of AmigaMail C= sent to me was May/June 1993, or did I miss something here ? – wkc – … via AP from Hamburg, Germany

#42160From: Wolf FaustAug 10, 1994 3:15 PM

Sorry, I don't know wich AmigaMail issue was last… But I wouldn't epxect anything from CATS soon… except a nice big invoice for the next 12 month developer status… Regarding ColorMaps: There is no article about ColorMaps in AmigaMail (at least none I found and I think I do have all AmigaMails). So you won't find it in the table of contents. However, there are one-two article that are indirectly related to ColorMaps and you can find many comments in the source code shown. Sorry, I don't know the issue… but it's not one of the latest issues. At least I got my knowledge about ColorMaps from those sample sources and AutoDocs… there is not much to know about those simple calls anyway… — Wolf Faust, Am Dorfgarten 10, 60435 Frankfurt, Germany —

#42165From: Werner KazmierzakAug 10, 1994 9:34 PM

Wolf, thanks for the info… BTW, C= hasn't invoiced me yet for developer support, although they normally should have done since early July. Maybe I'll EMail Dr. K. and ask him what's going on. – wkc – … via AP from Hamburg, Germany

#42290From: Gerald BonnstetterAug 19, 1994 6:28 AM

Werner, The US CATS program on BIX has stated that they are not sending out any developer renewals or accepting new applications. The developer conferences on BIX are also staying open for now and are not droping or adding anyone to those closed conferences. The above may only apply to US and North American developers, but it could be the same for German developers. If you EMail Dr. K. you should let us know what he says. // \X/ Amiga or bust! Gary Bonnstetter, Bonnsoft

#42129From: Vic WagnerAug 7, 1994 4:53 PM

Michael, 127L<<<24 isn't what you want anyway.

#42135From: Michael WilliamsAug 8, 1994 12:17 PM

Vic, I thought 127L<<<24 executes faster 😉

#42146From: Vic WagnerAug 8, 1994 11:40 PM

Michael, executes faster than what? You're getting the wrong number.

#42151From: Michael WilliamsAug 10, 1994 12:58 AM

Vic Your message read: 128L<<<24 is not what you … — To which I responded: … executes faster 😉 — Note the <<< in your message and the 😉 in mine. Who's getting the wrong number? Mike

#42168From: Vic WagnerAug 11, 1994 1:00 AM

You won't get the 'correct' number if you 128L<<24 you really want to: 128 * 0x1010101

#42202From: Wolf FaustAug 13, 1994 6:09 AM

Hey, that's also a neat way doing a multiplication instead of doing the shift's I'm currently using… (well, not really important for my application… but I never though of it…). — Wolf Faust, Am Dorfgarten 10, 60435 Frankfurt, Germany —