Hello, I know about the tiled maps but this game I think used another kind of stuff to works and check the collisions, so the map is not done using tiles and the level floor it does'nt have the same height all the time.

In my opinion it looks that the collision with the ground is done using a kind of 2d polygons so I was trying to find a map editor in internet using polygons but i didn't find. About the level map... mm.. maybe the level is done drawing the complete map, I don't know.

Do you know any software to do "2d polygons maps" and how was done the level for yoshi's ilsand?

Regards

I don't know exactly how those things were done in Yoshi's Island, but I don't think that it used a polygons. SNES hardware is really old and the development was made directly on assembly language and there are no abstractions like "polygons", it's all about bytes, bits, registers and everything depended a lot on the hardware.

Also, consoles of that time did a lot of the work with hardware, so probably the detection was made by the hardware checking if sprites overlaped. I know the NES did it that way, so I guess the SNES did something similar.

The levels were also drawn in a different way than modern games, again depending a lot on the hardware, so it probably wasn't a full level drawn completely, the hardware wouldn't support such thing and it would make a lot of wasted resources.

If you want info to make something similar to Yoshi's Island I'd recommend you find a modern game that's already similar and research how that game was made. It would be a lot easier to find information that way, unless you want to make a game for the SNES too (you can write one and play it on emulators).

Do you know any software to do "2d polygons maps"

GLEED2D is one. There are others that I don't remember the names of.

Thanks for the info it was very usefull. DiegoSLTS yes, it's for a modern game I just know how to do tiled map games with a fixed size tiled, I use this tool:

so I was wondering how other kind of 2d games are done that have different style.

Ground collisions in YI are most definitely tile-based.

HOWEVER, it is not a simple binary system where tiles are either solid or not - instead they have a wide variety of different tile types.

For example, Mega Man X has different tile types to represent different sloped tiles - when the player collides with a slope tile, the game can determine from the tile type and the player's x-coordinate what the actual ground height is at that location.

Also note that most such games do not do full bounding-box collisions with the ground, but instead use a small number of single-pixel "sensors", because it's faster to test single points against a tile map rather than whole bounding boxes.

Also, consoles of that time did a lot of the work with hardware, so probably the detection was made by the hardware checking if sprites overlaped. I know the NES did it that way, so I guess the SNES did something similar.

Actually collision detection on both NES and SNES was done entirely via software.

The NES' "hardware collision detection", such as it is, is strictly limited to determining if sprite index 0 is overlapping non-transparent background pixels - it's only real purpose is as a timing marker for raster effects.

Nice

For example, Mega Man X has different tile types to represent different sloped tiles - when the player collides with a slope tile, the game can determine from the tile type and the player's x-coordinate what the actual ground height is at that location.

Sonic use the same I think in the curve tiles.

I thought that yoshi's island map is like earthworm jim? Are the earthworm jim maps tiled-based too? And do you know any example of tilesets that use these technique so i can imagine it?