Full-screen overscan on KS1.3?

[Warty]

I'm trying to display a full overscan HAM-6 image at 368x462. I'm targeting 1.3 for this game, and am coding in C. I am opening a new custom screen, and a backdrop window, and loading the graphic into that window's RastPort. The window starts at 0,0. RKM says:

LeftEdge, TopEdge
The LeftEdge and TopEdge variables give the position of the screen relative to the upper left corner of the monitor’s visible display (as set by the user in the Overscan preferences editor). If it is positioned down or to the right, the values are positive. If the screen is positioned up or to the left, the values are negative. The values are in screen resolution pixels. In systems prior to V36, LeftEdge positioning is ignored and negative TopEdge positions are illegal.

and, of course, it looks fine on UAE, but on real hardware, the bottom and right edges are totally cut off, because it didn't actually position itself to start in the overscan area. Admittedly, my A3000 is displaying this, and it has an indivision in it, so that has some impact I can't describe.

I had to turn the HAM image loading off in low memory situations, so on my unmodified A1000, I don't know what it would do exactly.

First screenshot is of it on A3000 hardware booted to 1.3, second is UAE with emulated A3000 using 3.2.1.

Any pointers?

[Warty]

I found this snipped in an AmigaWorld Tech Journal article (see attachment). Basically it says people used various hacks to do this before the 2.0 ROMs. I'm not sure how to search for stuff like that. Pre-internet. I don't have any early Amiga magazines.

hmm. Maybe Fred Fish...

[saimon69]

Maybe looking for the transactor magazines online? I know a lot of dev topics were there

[Warty]

In case anyone needs this in the future, the answer is basically this:
- you can't create the screen in 1.3 with any offsets
- 1.3 knows about dxOffset, dyOffset, but they can't be set after the fact.
- you need to create a new View, configure it, then LoadView() it into existence.

A couple of examples to look at:
- https://wiki.amigaos.net/wiki/Classi...ics_Primitives
(look at the example under "Loading and Displaying the View")
- aminet: HamPics. http://aminet.net/package/pix/misc/HamPics

/*

 * loadpic.c - ILBM loader which runs from the workbench

 *

 * Written by Jonathan Hue - if you decide to steal some of this

 * code (yeah, like anyone would want to), give me credit.

 */