Multitouch Touches Detection

Solar2D General Questions/Discussion
#1

Hello everyone. 

Is there a way I can track the x and y coordinates of each simultaneous touch?

#2

Here’s the best tutorial to handle this:

http://docs.coronalabs.com/guide/events/detectEvents/index.html

Short answer: using a Runtime listener with print functions showing event.x and event.y would work well.

#3

Ok but, if multitouch is enabled, event.x and event.y should be tables containing all the simultaneous positions, shouldn’t they?  The point is that, since multitouch doesn’t work on the simulator and I don’t have a mac (Xcode to handle the multitouch) I cannot test it with the terminal (I know, I’m lazy)

#4

If I’m understanding you correctly, I think you want to keep track of the points you touch. To do this, you’d need to add each touch into a table, as they aren’t automatically entered. If I misunderstand, let me know.

#5

No. If I want to get the x-coordinate of a point when multitouch is DISABLED, e.x returns a SINGLE value, let’s say 130. But if multitouch is ENABLED I may guess that e.x will be a table containing all the x-coordinates of the points being touched at an instant. Am I correct?  (Thank you for your patience)

#6

Ah, I think I understand. I have to assume the coordinates would be recorded; I do not know how you would access that record without creating your own record-keeping function. I think it would just be better to create your own function to throw every x touch coordinate into a table to access at your leisure.

I can tell you for a fact that Corona SDK built-in multi-touch wasn’t ideal when I first implemented it for my apps, so I had to use a bunch from the code exchange until I found the best mix. Here’s the one that I’m the biggest fan of. It seems complicated at first, but it’s the best solution that I found.

http://developer.coronalabs.com/code/dmc-lib-touch-manager

#7

Thank You

#8

Here’s the best tutorial to handle this:

http://docs.coronalabs.com/guide/events/detectEvents/index.html

Short answer: using a Runtime listener with print functions showing event.x and event.y would work well.

#9

Ok but, if multitouch is enabled, event.x and event.y should be tables containing all the simultaneous positions, shouldn’t they?  The point is that, since multitouch doesn’t work on the simulator and I don’t have a mac (Xcode to handle the multitouch) I cannot test it with the terminal (I know, I’m lazy)

#10

If I’m understanding you correctly, I think you want to keep track of the points you touch. To do this, you’d need to add each touch into a table, as they aren’t automatically entered. If I misunderstand, let me know.

#11

No. If I want to get the x-coordinate of a point when multitouch is DISABLED, e.x returns a SINGLE value, let’s say 130. But if multitouch is ENABLED I may guess that e.x will be a table containing all the x-coordinates of the points being touched at an instant. Am I correct?  (Thank you for your patience)

#12

Ah, I think I understand. I have to assume the coordinates would be recorded; I do not know how you would access that record without creating your own record-keeping function. I think it would just be better to create your own function to throw every x touch coordinate into a table to access at your leisure.

I can tell you for a fact that Corona SDK built-in multi-touch wasn’t ideal when I first implemented it for my apps, so I had to use a bunch from the code exchange until I found the best mix. Here’s the one that I’m the biggest fan of. It seems complicated at first, but it’s the best solution that I found.

http://developer.coronalabs.com/code/dmc-lib-touch-manager

#13

Thank You

#14

Sorry guys…

I read all of this, and still I don’t get it.

I copy the “dmc_touchmanager.lua” and I have my iPad to test it but nothing happens…

I have this

-- setup our function-type event handler -- local handler = function( event )           local target = event.target           if event.phase == 'began' then                   -- set focus if object should always receive this event                 TouchMgr:setFocus( target, event.id )           elseif event.phase == 'moved' then                      -- do stuff here                 local txPlay1 = display.newText( "I hope it works?", display.contentCenterX - 67, display.contentCenterY - 140, 300, 0, native.systemFont, 46 )                 group:insert(txPlay1)                     txPlay1:setTextColor(255)           elseif ( event.phase == 'canceled' or event.phase == 'ended' ) then                   -- unset focus when done                 if event.isFocused then                         TouchMgr:unsetFocus( target, event.id )                 end         end           return true end   local o = display.newRect( 350, 700, 300, 300 ) o:setFillColor( 255, 255, 255 )   TouchMgr:register( o, handler )

and I require this

local TouchMgr = require( "dmc\_touchmanager" )

nothing…

The idea it’s to create a BIG image with a map

and when people “Pinch” their fingers the image will scale down to a small size

if the “pinch” their fingers they can make the map bigger…

or scroll the image to see many areas of the map.

a common thing that you see in many games…

please help me out to make this work

#15

@ Victor: ‘dmc_touchmanager’ isn’t for ‘pinch&zoom’.
What you want to do involves mildly-complex group&layer calculations.
Here is the camera module I use: http://developer.coronalabs.com/code/perspective
If you scroll down in the comments section you’ll see a few people that are using a ‘pinch&zoom’ feature.

Hope this helped.

-Saer

#16

Sorry guys…

I read all of this, and still I don’t get it.

I copy the “dmc_touchmanager.lua” and I have my iPad to test it but nothing happens…

I have this

-- setup our function-type event handler -- local handler = function( event )           local target = event.target           if event.phase == 'began' then                   -- set focus if object should always receive this event                 TouchMgr:setFocus( target, event.id )           elseif event.phase == 'moved' then                      -- do stuff here                 local txPlay1 = display.newText( "I hope it works?", display.contentCenterX - 67, display.contentCenterY - 140, 300, 0, native.systemFont, 46 )                 group:insert(txPlay1)                     txPlay1:setTextColor(255)           elseif ( event.phase == 'canceled' or event.phase == 'ended' ) then                   -- unset focus when done                 if event.isFocused then                         TouchMgr:unsetFocus( target, event.id )                 end         end           return true end   local o = display.newRect( 350, 700, 300, 300 ) o:setFillColor( 255, 255, 255 )   TouchMgr:register( o, handler )

and I require this

local TouchMgr = require( "dmc\_touchmanager" )

nothing…

The idea it’s to create a BIG image with a map

and when people “Pinch” their fingers the image will scale down to a small size

if the “pinch” their fingers they can make the map bigger…

or scroll the image to see many areas of the map.

a common thing that you see in many games…

please help me out to make this work

#17

@ Victor: ‘dmc_touchmanager’ isn’t for ‘pinch&zoom’.
What you want to do involves mildly-complex group&layer calculations.
Here is the camera module I use: http://developer.coronalabs.com/code/perspective
If you scroll down in the comments section you’ll see a few people that are using a ‘pinch&zoom’ feature.

Hope this helped.

-Saer