How to setup a smooth character jump with physics?

Solar2D Lua Language
#1

Hello guys,

I am working on an endless runner where i need my hero to jump from rock to rock (rock changes in length randomly. I am using physics for collisions (hero to rocks and hero to flying obstacles) I am trying to figure the best way to implement a jump  I am not too worry about the logic of the single/double jump. I am mostly having hard with the jump itself. I have a look at many endless runner games and most of them have a nice and smooth jumps. I tried just using applyLinearImpulse inside a  touch event (so every time the player touch the screen, the hero gets a upward force and then with a timer later on gets an downward force. That seems to be a little too jumpy.

I also try the same impulse method but within a enterFrame. I detect a screen touch and I set variable (touchFlag) to true or false. The enterFrame then apply a force either upward or downward. It is much smoother but I do not want the player to simply keep his/her finger on the screen and stay in the air the all time!

I was wondering if someone could suggest a better to approach this problem. To help visualize what I am looking for, maybe you can check the following two apps:

I  like how smooth the hero’s jump:

https://itunes.apple.com/us/app/alien-life-race-anti-gravity/id606601428?mt=8

I like the double jumps in this game:

https://itunes.apple.com/us/app/disco-style-runner-free-saturday/id581348057?mt=8

THANK YOU!

Mo

ps: I am also not sure how density affect the movement. I also assuming that setting the hero bounce to zero means the hero will not bounce when hitting the rocks down below (or in the top of the screen)?

#2

If you have gravity set, then you don’t need to apply the second downward force, just apply a linear impulse upwards and gravity takes care of the rest. I’m in the middle of producing an endless runner and have my gravity set at 15, that gives a nice smooth jump arc.

#3

Hello Andy. Sorry for the delay. Unfortunately I do not use gravity in my game (many moving objects which will not work if there is gravity involved) I think I making progress. I will share when I happy with the result! Thanks again for taking the time Andy. Mo.

#4

I would suggest using gravity and set object.gravityScale=0 for all objects that shouldn’t be effected by it.

#5

WOW! I learn something new everyday! I did not know about gravity scale. I will try that.

THANK YOU!

Mo

#6

If you have gravity set, then you don’t need to apply the second downward force, just apply a linear impulse upwards and gravity takes care of the rest. I’m in the middle of producing an endless runner and have my gravity set at 15, that gives a nice smooth jump arc.

#7

Hello Andy. Sorry for the delay. Unfortunately I do not use gravity in my game (many moving objects which will not work if there is gravity involved) I think I making progress. I will share when I happy with the result! Thanks again for taking the time Andy. Mo.

#8

I would suggest using gravity and set object.gravityScale=0 for all objects that shouldn’t be effected by it.

#9

WOW! I learn something new everyday! I did not know about gravity scale. I will try that.

THANK YOU!

Mo