Scrolling...

[MidgetsBro]

I am making a project for school, that is kind of like a Zelda type game, but I need help. I don't know how to make it scroll. I want the levels to be bigger, but for now they are just 20x20 tiles. I would like maybe a 100x100 map, and just display 10x10 of the tiles. I'll attach it. Please tell me if there is a half-way easy way to implement scrolling to my code. If not, I will have to rewrite everything, and that's not fun.

Thanks
-Joey

[Fox]

well... no.

I recommend you to completely re-design the engine, starting with your graphics system... read my tutorial for assistance or review the scrolling demo.

[Arbiter]

Fox,

Every single one of your posts states...

"Read my tutorial"

Is there anything you don't have a tutorial for????

PS - have you tried Sentience yet?

[Fox]

as people asked me things again and again i wrote these tutorials..


yes i tried but erm.. didnt like it too much. im not a fan of strategy games

[Sastraxi]

im not a fan of strategy games

Aaaah! *Shocked and Apalled*

Seriously though, you could do it without redoing your engine, but it's a longshot. One way to do this is to add an Offset to your drawing function, and only draw the blocks needed. I haven't looked at your code but if you are using Directdraw you'll need to clip the RECTs before blitting them. I believe I gave you a sample code a while ago, did I not?

[MidgetsBro]

Fox - I have tried your tutorial many times. I just seem to get off track all the time and never finish it. I also don't learn much from demos where it's just the project. I'm not good at reading through the code, I would rather have somthing tell me what they are doing, then show me the code. But I'll have a look again, as soon as I get home (I'm at school).

I'm not using DirectDraw... just BitBlt. I just need a really simple game. If I cannot just add it to what I have already, I will just have a 20x20 or 25x25 map. Whatever fits in the screen at 1024x768. And I don't think you ever gave me any sample code Sastraxi. I know you've helped me with other things, but not this.

[Sastraxi]

Well since you're using BitBlt it wouldn't help anyways... But Scrolling itself is pretty simple. I should've given you some code before but here goes now:

Function Draw(OffsetX As Long, OffsetY As Long)
Dim X As Long
Dim Y As Long
Dim Ix As Long
Dim Iy As Long
 
    X = OffsetX
    Y = OffsetY
    
    For Ix = Int(X / [TileWidth]) To Int((X + ScreenW) / [TileWidth])
    For Iy = Int(Y / [TileHeight]) To Int((Y + ScreenH) / [TileHeight])
        [Draw Tile Function] Ix * [TileWidth] - OffsetX, Iy * [TileHeight] - OffSetY
    Next I
End Function

I believe this would work. You would pass pixel values as the offset, as in this example:

Draw PlayerX + (PlayerW / 2) - (ScreenW / 2), PlayerY + (PlayerH / 2) - (ScreenH / 2)