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Official docs of ct.js game engine
https://docs.ctjs.rocks/
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Update tut-making-platformer.md #12

Closed Eilandis closed 5 years ago

Eilandis commented 5 years ago

You named the crystal widget CrystalCounter in the tutorial, not CrystalsWidget. (also, the line ct.types.copy('CrystalCounter', 0, 0); does not appear on the screenshot below, and therefore is not explained)

In the last code snippet (better code for moving platforms), you look for the robot two times (var robot = ct.place.meet(this, this.x, this.y, 'Robot'); then robot = ct.place.meet(this, this.x, this.y - 1, 'Robot');). Is there any reason for that ?

Thanks for the tutorial ;)

CosmoMyzrailGorynych commented 5 years ago

Thanks for the fixes! Though it was supposed that the type was called "CrystalsWidget", and the real typo is at line https://github.com/ct-js/docs.ctjs.rocks/pull/12/commits/02cf39d26f9180a4b71e0600aadc77f2727000ae#diff-b17a7df3caa6d9cf99c4c9fda01cad96R497

In the last code snippet (better code for moving platforms), you look for the robot two times [...] Is there any reason for that?

Yes, there is. We have two clauses: when a robot overlaps with a platform and when it doesn't. If a robot does, then the platform can be walked through.

In the second case, when a robot does not overlap with a platform, the platform does not yet know about the existence of the robot, because ct.place.meet(this, this.x, this.y, 'Robot'); returns nothing. Thus, the robot is undefined as well. We need to search again, above the platform, if we want to move our robot. As we have pixel-perfect collisions, a lookup at one pixel above the platform is enough. robot = ct.place.occupied(this, this.x, this.y - 1, 'Robot'); finds a robot that is standing right on top of the platform, so the variable robot can be defined (and used) once again.

I'll push the fixes for CrystalsWidget and a better explanation of the platform code in the nearest time.