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c#2dxna-4.0z-ordertop-down

2D Depth System Method XNA C#

I am creating a 2D Top-Down RPG game like the Legend of Zelda: A link to the past.

when the player is drawn i want to update the tree depth so that it is over and under the player when the player Y position is higher or lower than the trees Y position, i think whether the tree is on top or not should be decided by the players Y position, being lower or higher. is it possible to do this in this way? can i change the layer depth in the update method?

I'm not sure you can. i'm not very experienced when coding. If there's a right way of doing this even without useing the spriteBatch layer depth i would appreciate any help.

I have discovered how to use the layer depth in the 

spriteBatch.Draw();

Method.

What i am attempting to do is shown in the images below

Woman in Front of Tree

Woman Behind Tree

The code i am using to separate trees from grass tiles uses layer depth like below:

spriteBatch.Begin(SpriteSortMode.FrontToBack, blendState = null, samplerState = null, DepthStencilState.DepthRead);

spriteBatch.Draw(tree, treePos, null, null, Vector2.Zero, 0, null, Color.White, SpriteEffects.None, 0.6f);

spriteBatch.End();

Tile draw method for the 

tile

has the float value set 

0.5f

Drawn image line with values and meanings

Solution

  • Here's a way to do it:

    Slice your sprites and do tile-based rendering, starting from the ground up to the sky.

    Say you have a tile grid whose each is 32*32 pixels, if you have a tree that is 32*96 pixels, then when sliced it will be like:

    A // layer 2
A // layer 1
A // layer 0 (floor)

    Logic:

    • draw all tiles on floor 0
    • draw all tiles on floor 1
    • etc ...

    Then obviously the part that should hide your player will be drawn correctly (before, if player is behind).

    (note that the lowest tile of the tree should not be walk-able)