next »

[k0tn]

Anyone know if it would be possible to have a parallax background using Polycode? Thank you!

[mcc]

There are several ways you could do this. Can you give some information about how you are drawing, currently?

If I wanted to do this, I would probably make all the foreground a child of entity A, the parallax backgrounds children of entities B and C, and then move entities A, B and C at different rates when the "camera" moves. Does that make sense?

Also I think maybe this would be better served either in Technical, or maybe even on the Polycode forum.

[BlueSweatshirt]

Personally I would write a small parallax manager class. You pass it images and have it update the positions of the images based on a given z-value when the camera moves.

[k0tn]

Also I think maybe this would be better served either in Technical, or maybe even on the Polycode forum.

Sorry I thought I did put this in there... but apparently not

[Rob Lach]

Personally I would write a small parallax manager class. You pass it images and have it update the positions of the images based on a given z-value when the camera moves.

Wouldn't a manager be overkill? Just tack on a "parralax ratio" and multiply it against your current camera coords.

[BlueSweatshirt]

Overkill? The idea I have for it in my head is pretty simple. I think it'd be simpler and cleaner than writing an entire parallax image class, but that's just me. And aside from those two relatively loose methods I don't really know how you'd implement it.(well, of course you could hardcode them into your game loop or something, but that'd be the same concept just without the OOP abstraction)

[zengeek]

Best way that i know of is using stack based transformations of camera. Pseudo-code:

Code:

for each parallaxLayer in layers
                using camera with translation(-camPos.X * parallax_layer.scrollspeed, -camPos.Y  * parallax_layer.scrollspeed)) {
                    for each sprite in parallax_layer.Sprites) {
                        renderer draw_sprite([somewhere], sprite);
                    }
                }
            }

Where scrollspeed is a value between 0 and 1. And using camera is a method that pushes the current transform prepends a new transform and pops when leaving scope. 
Yeah that's in engine level.