Sprite warping (or wraping?)

[System64]

Hi,

You don't need 4 sprites to warp in both directions, just 2 sprites. Here is the simplified source.

Beware that you cannot warp in both axis at the same time, that is, trying to warp in a corner breaks the logic rules. You should restrict your gameplay to avoid reaching a corner!

Hi
Effectively, you only need 2 sprites if you are not taking corners in consideration. I considered the case with the corners but I didn't precised about that, I am sorry. For this specific case, you need 4 sprites.

About the circle algorithm, I made a varient that let you make a filled circle, it works very well.

Code:

proc drawCircleFill(bitmap: TLN_Bitmap, centerX: int, centerY: int, radius: int): void =
    var
        x = 0
        y = radius
        m = 5 - 4 * radius

    while (x <= y):
        bitmap.drawLine(centerX - x, centerY - y, centerX + x, centerY - y)
        bitmap.drawLine(centerX - y, centerY - x, centerX + y, centerY - x)
        bitmap.drawLine(centerX - y, centerY + x, centerX + y, centerY + x)
        bitmap.drawLine(centerX - x, centerY + y, centerX + x, centerY + y)

        if (m > 0):
           
            dec y
            m -= 8 * y;
        inc x
        m += 8 * x + 4

proc drawLine(bitmap: TLN_Bitmap, x: int, y: int, x2: int, y2: int): void =
    var
        dy = y2 - y
        dx = x2 - x
        err = 2 * dy - dx
        myY = y

    for myX in x..x2:
        bitmap.getBitmapPtr(myX, myY)[] = 1

        if err >= 0:
            myY += 1
            err -= 2 * dx
       
        err += 2 * dy

I also have a suggestion for tiles. I noticed there is still 5 unused bits in the tile struct, so you maybe can add a blending flag for individual tiles, so you can enable or disable transparency for individual tiles, unless you planned something else with thoses bits? What do you think about this idea?