start physics without require "physics" if there is require "composer"

Solar2D General Questions/Discussion
#1

Hi,

It seems that we can start physics without requiring physics if we already require composer. The following code works:

local composer = require "composer" physics.start()

Is it a bug or something by design?

Thanks,

Lin

#2

Hi Lin,

This doesn’t seem correct. Are you sure it’s actually starting the physics engine? Are you able to create physics objects after that and does it work as expected?

Brent

#3

Interesting. I’m going to try it with an empty project folder and see what happens.

#4

Is it possible that physics has already been required and declared as a global variable in another file?

#5

Hi Brent and all,

I have only one file and you can try below:

local composer = require "composer" physics.start() local circle = display.newCircle(display.contentWidth/2, 50, 20) local line = display.newRect(display.contentWidth/2, display.contentHeight/2, display.contentWidth, 10) physics.addBody(circle) physics.addBody(line, "static")

No error at all, the circle just drop and hit the line. I’m using current public release (build 2014.2511). Removing “require composer” will generate error.

Regards,

Lin

#6

physics has “always” (at least since i first began using Corona years ago) leaked a global “physics”. try this:

local not\_physics = require("physics") -- unusual reference name physics.start() -- tah dah!

or even simpler, this:

require("physics") -- no reference name at all physics.start() -- tah dah!
#7

Hi Lin,

This doesn’t seem correct. Are you sure it’s actually starting the physics engine? Are you able to create physics objects after that and does it work as expected?

Brent

#8

Interesting. I’m going to try it with an empty project folder and see what happens.

#9

Is it possible that physics has already been required and declared as a global variable in another file?

#10

Hi Brent and all,

I have only one file and you can try below:

local composer = require "composer" physics.start() local circle = display.newCircle(display.contentWidth/2, 50, 20) local line = display.newRect(display.contentWidth/2, display.contentHeight/2, display.contentWidth, 10) physics.addBody(circle) physics.addBody(line, "static")

No error at all, the circle just drop and hit the line. I’m using current public release (build 2014.2511). Removing “require composer” will generate error.

Regards,

Lin

#11

physics has “always” (at least since i first began using Corona years ago) leaked a global “physics”. try this:

local not\_physics = require("physics") -- unusual reference name physics.start() -- tah dah!

or even simpler, this:

require("physics") -- no reference name at all physics.start() -- tah dah!