Tile engine

[Fox]

Say in your scrolling function you have 2 variables, one stores the scrolling offset (intScrollX ?) and one stores the tile offset (intTmpX ?) and a tile size of 20 pixels (must match)...

intScrollX = intScrollX + 1
If intScrollX > 20 then
   'Reset scrolling offset
   intScrollX = 0
   'Adjust tile offset
   intTmpX = intTmpX + 1
Endif

Remember where you draw the map you have to add both offsets to draw it at the correct position:

For A = 0 to MapWidth
For B = 0 to MapHeight
   DrawTile Map(intTmpX,intTmpY), A*TileWidth - intScrollX, B*TileHeight - intScrollY
Next
Next

That's all ..

[McCain]

intSclX is the scroll offset, intScrollX is the tile offset
intTmpX is the tile the player is on...
Fox, I studied the example you gave me - it's exactly what I got allready...

[Fox]

If you had the same it worked

intPX = intPX + 20 'What the hell do you need intPX for?
         If intTmpX >= 20 + intScrollX Then 'Why do you check the player position :confused:
            intScrX = intScrX + 20 'intSrcX? You don't need thisat all!
            If intSclX < 20 Then 'Next tile reached right?
                intSclX = intSclX + 20 'Why 20? Scrolling is 1 pixel / frame I assume...
            ElseIf intSclX >= 20 Then 'Well .. again checked that we reached the next tile or what?
                intScrollX = intScrollX + 1 'Increase tile index
                intSclX = 0 'Reset scrolling
            End If
        End If

[Fox]

hrrr I took the time to correct your code:

If GetAsyncKeyState(vbKeyRight) <> 0 Then
    If intMap(intTmpY, intTmpX + 1) = 0 And intMap(intTmpY2, intTmpX + 1) = 0 Then
        intPX = intPX + 20 'Still dunno what's this..
 
        intSclX  = intSclX +1
        if intSclX >20 then
           intSclX =0
           intScrollX =intScrollX +1
        endif
    End If
End If

intMap(intTmpY, intTmpX + 1)

not sure how this'll work though.. it means your tiles are 1x1 pixel in size! If you had 20x20 tiles you'd need to do collision it like this:

intMap(int(intTmpY/20), int(intTmpX/20) + 1)

etc.

[McCain]

intPX is an integer variable holding the X position of the character... That's what I use to move the character when the map isn't scrolling...
Maybe if I had posted this piece of code it would've been easier to understand...

intTmpX = intPX \ 20
intTmpY = intPY \ 20
intTmpY2 = (intPY \ 20) - 1

And I think I just figured out what's wrong with the collision thing, thanks Fox!
When the map is scrolling and the character isn't moving the intPX and intPY doesn't get updated so the intTmpX and intTmpY stays the same...

[/\/\isanThr0p]

So how's everything going?
I don't know if I mentioned of course the actor needs to be drawn different too now or it won't scroll with the map
you draw it like:

draw x-intScrollX*20+xscrl,....

[McCain]

I'm going away for the weekend so I can't do any coding...
I uploaded what I got if anyone wanna have a look...
When I get the scrolling to work I want to add gravity

[/\/\isanThr0p]

well adding gravity is really simple... here you go:
first you need to check if you actor is standing on something if so yspeed=0 if not just add 9.8 to yspeed
and every loop you go like
y=y+yspeed
x=x+xspeed

that way you can also implement jumps and stuff
jump just set y speed to some negativ value big enough and you will get a nice parabolic jump...
that way you can also do it for going left and right so you actually need to hold down the key a while till you reach full speed and also you can make it so the actor is not able to stop at once but slides a little...
in one of my games I made the xspeed increasement dependend on the ground I was standing on to get ice and stuff like that...

[Zaei]

9.8 pixels looks wrong. Add 9.8*heightOfActor, instead =).

Z.

[/\/\isanThr0p]

hm got another idea what you could do...
what about a paralax background? I think it's pretty cool having one, I never made one though.
It should not be to hard though. smaller things in the back move slower and bigger things in front of the game move real fast so they seem all close...

[/\/\isanThr0p]

you are right 9.8 pixels does not work... you need some scale down thingy... I often used constants from nature and took some general "scale down" variable to finetune the game easily...

[McCain]

Ok, I'm back.
Gravity doesn't look too hard, but before I implement that I want to get the scrolling to work...