Scrolling object on screen in scroll plan

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matteus
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Joined: Mon Feb 04, 2008 1:41 pm

Scrolling object on screen in scroll plan

Post by matteus » Mon Sep 26, 2016 8:10 pm

Right ok so I can get a block of tiles to scroll off screen but not on! What am I missing? :) Could someone show me an example?

Code: Select all

void processStartScreen() {
    switch(GameVariables.StartScreenStage) {
    case 0:
        SYS_disableInts();
        VDP_drawText("Press Start", 1, 0);
        SYS_enableInts();
        SYS_disableInts();
        VDP_drawImageEx(PLAN_B, &title_layout, TILE_ATTR_FULL(PAL1, FALSE, FALSE, FALSE, ind), 153, 26, TRUE, TRUE);
        nextvpos = 0;
        GameVariables.StartScreenStage = 1;
        SYS_enableInts();
    break;
    case 1:
        nextvpos++;
        SYS_disableInts();
        VDP_setVerticalScroll(PLAN_B, nextvpos);
        SYS_enableInts();
    break;
    }
}

matteus
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Posts: 336
Joined: Mon Feb 04, 2008 1:41 pm

Re: Scrolling object on screen in scroll plan

Post by matteus » Mon Sep 26, 2016 8:12 pm

Okay this code works now :D but is there a better way to do it?

Stef
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Re: Scrolling object on screen in scroll plan

Post by Stef » Tue Sep 27, 2016 8:32 am

I don't really understand what you mean by " get a block of tiles to scroll off screen but not on!" ?
VDP_setVerticalScroll(..) or VDP_setHorizontalScroll(..) are the methods to use for hardware scrolling, you can use positives or negatives values depending how you want to scroll you plan. If you scroll all over the plan size then you might refresh part of your plan which is currently off screen.

matteus
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Posts: 336
Joined: Mon Feb 04, 2008 1:41 pm

Re: Scrolling object on screen in scroll plan

Post by matteus » Wed Sep 28, 2016 10:07 am

I was struggling with whether the measure was in tiles or pixels! :)

Stef
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Re: Scrolling object on screen in scroll plan

Post by Stef » Wed Sep 28, 2016 12:00 pm

So i guess you realized they are in pixels ;)

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