Physics: isSensor am I understanding it correctly?

Getting Started Newbie Questions
#1

Hi, I just recently, as in today, found out about Corona. I’m using the trial ware and I’m trying to figure out a problem I’m having. I defined a rectangle display.newRect() that I can move around using a touch event, and then I added physics and had a crate drop from the top of the application. I don’t want this rectangle to be part of the physic world so I read the docs and it said to use physics.addBody( rect, { isSensor=true} ) so that the object will send a collision message but not interact with the object.

The problem is I have a ground defined but as soon as the game starts this rectangle which is newRect falls through the world, pass the ground into oblivion. If I add physic parameters to this rectangle it falls to the ground, not phase through the ground.

Am I understanding the function of isSensor correctly? I want an invisible trigger, which doesn’t move or interact with the world, in which I can handle an event by something else passing through it, this time a rectangle, and have that call the collision handler and do whatever inside of it.

Thanks again, and I’m looking forward to getting to know all of you. [import]uid: 10832 topic_id: 3250 reply_id: 303250[/import]

#2

physics.addBody( recti, “static”,{})
you need to add the static option [import]uid: 7911 topic_id: 3250 reply_id: 9645[/import]

#3

Ps welcome to corona vie been here for about 3 weeks and loving it [import]uid: 7911 topic_id: 3250 reply_id: 9647[/import]

#4

Hello, you still have to specify a body type even if it is a sensor object. Body types include:

  • dynamic (default); will react to gravity

  • static; will not react to gravity

  • kinematic; probably the least used

I suggest trying this:

physics.addBody( rect, “static”, { isSensor=true} )

Also, welcome to Corona!

UPDATE: Looks like jstrahan beat me to it! [import]uid: 7849 topic_id: 3250 reply_id: 9646[/import]

#5

Wow, I am very impressed with the quickness and thoroughness of your replies. Plus, they were very polite and welcoming as opposed to ‘RTFM the manual nub’. I did RTFM but all I saw was a reference to isSensor and that didn’t have ‘static’ in it. Thank you for the answer, can’t wait to try it when I’m off work.

@jstrahan I’ve been here literally for 3 hours, when I posted this question, and I’m loving it! The product looks solid and the community is great. And, thank you for the welcome.

The only thing I would recommend is better search. I tried entering isSensor and only came up with the example in the online manual that didn’t have a body type assigned.

*EDIT* I’m stupid I noticed that there is a separate search box for the forums on the forums. [import]uid: 10832 topic_id: 3250 reply_id: 9683[/import]

#6

I find that reading through the API is very helpful in fact I keep them open in a tab the whole time [import]uid: 7911 topic_id: 3250 reply_id: 9686[/import]

#7

I use a Firefox plugin called ‘ScrapBook’ which allows me to save a webpage to a separate ‘ScrapBook’ menu in the browser (it’s placed right next to bookmarks), and what I did was open up every page of the documentation (there’s not THAT many, and I skipped on the one’s labeled “Corona (old)” and then saved it with Scrapbook.

It gives me offline access, and then when I need to look something up real quick, it loads MUCH faster than usual. The only downside is you have to re-do it every so often if you want to make sure they’re updated, but like I said, there’s not that many separate pages so not too bad. [import]uid: 7849 topic_id: 3250 reply_id: 9704[/import]

#8

Thanks for the tip, and good games jonbeebe. It is exciting to know that you still give back and participate with the community. I hope I can just receive a fraction of the success you have, but I’m mostly doing this as a hobby and/or resume builder. I just want to be able to say ‘look at what I’ve done’. [import]uid: 10832 topic_id: 3250 reply_id: 9722[/import]

#9

@scontapay: Thanks for your comments! I’m glad you like our games and I wish you the best of luck with your projects, maybe it’ll turn into something more than just resume stuff one of these days, who knows? :slight_smile:

Anyway, if you’re on twitter, we’re @beebegames … feel free to send a tweet and we’ll be sure to follow you back. [import]uid: 7849 topic_id: 3250 reply_id: 9738[/import]