Preliminary results: Converting real-world app

[ingemar]

EDIT : (Nov 2, 2013) All issues reported in this old post have been fixed.

I’ve taken one of my published apps and converted it to Graphics 2.0 (as far as is currently possible).

Apart for some issues (more on that later), I’ve gotten it functional.

Most of the work that needed to be done came down to 2 things:

1. Changing setReferencePoint to object.anchorX and object.anchorY

2. Deciding which display-groups to leave as-is or convert to containers/snapshots

NOTES:

The deprecated sprite.* API is gone, so you’ll need to use the new API if you aren’t already doing that.

ISSUES in Graphics 2.0:

1. No support for the newer table style params for newText

2. Can’t rotate stage around center of screen (see comments below)

3. Line objects do not accept image strokes

4. Objects that are not visible do not receive events even though isHitTestable is set to true

5. Physics objects do not take anchor point into consideration (affects collision detection)

(All of the above issues have separate threads in this forum section)

No device testing has been done as it’s not functional in the current build, so testing has only been done in the Corona Simulator.

I’ve also noticed rendering issues with some containers that are nested within multiple display groups. Some (not all) containers fail to crop their contents within the bounds. I’ve tried to write a test-case for this issue, but it behaves as expected when doing so, which means I’ve stumbled upon some edge-case in my production code. I’ll keep monitoring this issue in later builds…

[walter]

Thanks for the feedback! And for the issues — we’ll add them to the list.

We’re working to improve v1compatibility mode to ease the conversion of reference points.

Also, containers cannot be infinitely nested b/c they use a mask. So as with graphics 1.0, you have to be careful about the number of levels of nested masks. In 2.0, you cannot to exceed 3 levels of nested masks (this includes text objects, masks on groups, and containers).

[walter]

For #4 (Objects that are not visible do not receive events even though isHitTestable is set to true), can you send us a test case?

We ran a quick test case using the “world.jpg” image from HelloWorld and the touch listener does seem to get called, as expected (below).

So curious to know if your test case is more complicated?

local background = display.newImage( "world.jpg" ) background.x = 160 background.y = 240 background.isVisible = false background.isHitTestable = true background:addEventListener( "touch", function(event)     print( event.phase, event.x, event.y ) end )

[ingemar]

Looks like I have some sort of edge case in my production code as your test-code works here as well…

(I use a newRect instead of an actual image, but still, it works.

I’ll investigate and report back here…

[ingemar]

OK… found it.

It turns out that if I set the fill color to transparent it fails to register taps even if isVisible = true.

(Don’t ask me why I did that, as I have no idea ;). However it works in Graphics 1.0)

local background = display.newRect(10, 10, 100, 100) background:setFillColor(1, 0); background.x = 160 background.y = 240 background.isVisible = true background.isHitTestable = true background:addEventListener( "touch", function(event) print( event.phase, event.x, event.y ) end ) 

[admin1]

Regarding #2: Can’t rotate stage around center of screen

In DP2, if you set v1 compatibility mode on (via config.lua), you should be able to rotate the stage about the center of the screen (v1 mode only) b/c we’ve restored ref pt in that mode.

[ingemar]

Regarding #2:

Sorry, but having to set V1 compatibility is not a long-term solution. This would mean that *all* future apps made with Corona would have to be set in V1 compatibility mode to behave properly on iOS, which can’t be right.

I’ve explained in more detail here:

http://forums.coronalabs.com/topic/38169-animated-autorotation-in-graphics-20-not-possible/

[walter]

That was a solution for pre-existing, legacy apps.

For pure-v2 apps (i.e. new code you are writing) you have several alternatives:

* Translate the origin of the stage to the center of the screen. And then place all children in that group.

* Create a group that’s positioned at the center on the screen.

[ingemar]

@walter

I guess Option 1 would be OK. If I understand this correctly I’ll then have a true Cartesian coordinate system with (0,0) at the center of the screen, right?

[walter]

Yea.

BTW, your suggestion on the other thread made me wonder if there were a camera concept that could be introduced that would encapsulate this somehow. 

[ingemar]

Item 2 can be crossed off the list.

No proprietary code needed any more for animated auto-rotation of the stage on iOS.

[walter]

Thanks for the feedback! And for the issues — we’ll add them to the list.

We’re working to improve v1compatibility mode to ease the conversion of reference points.

Also, containers cannot be infinitely nested b/c they use a mask. So as with graphics 1.0, you have to be careful about the number of levels of nested masks. In 2.0, you cannot to exceed 3 levels of nested masks (this includes text objects, masks on groups, and containers).

[walter]

For #4 (Objects that are not visible do not receive events even though isHitTestable is set to true), can you send us a test case?

We ran a quick test case using the “world.jpg” image from HelloWorld and the touch listener does seem to get called, as expected (below).

So curious to know if your test case is more complicated?

local background = display.newImage( "world.jpg" ) background.x = 160 background.y = 240 background.isVisible = false background.isHitTestable = true background:addEventListener( "touch", function(event)     print( event.phase, event.x, event.y ) end )

[ingemar]

Looks like I have some sort of edge case in my production code as your test-code works here as well…

(I use a newRect instead of an actual image, but still, it works.

I’ll investigate and report back here…

[ingemar]

OK… found it.

It turns out that if I set the fill color to transparent it fails to register taps even if isVisible = true.

(Don’t ask me why I did that, as I have no idea ;). However it works in Graphics 1.0)

local background = display.newRect(10, 10, 100, 100) background:setFillColor(1, 0); background.x = 160 background.y = 240 background.isVisible = true background.isHitTestable = true background:addEventListener( "touch", function(event) print( event.phase, event.x, event.y ) end ) 

[admin1]

Regarding #2: Can’t rotate stage around center of screen

In DP2, if you set v1 compatibility mode on (via config.lua), you should be able to rotate the stage about the center of the screen (v1 mode only) b/c we’ve restored ref pt in that mode.

[ingemar]

Regarding #2:

Sorry, but having to set V1 compatibility is not a long-term solution. This would mean that *all* future apps made with Corona would have to be set in V1 compatibility mode to behave properly on iOS, which can’t be right.

I’ve explained in more detail here:

http://forums.coronalabs.com/topic/38169-animated-autorotation-in-graphics-20-not-possible/

[walter]

That was a solution for pre-existing, legacy apps.

For pure-v2 apps (i.e. new code you are writing) you have several alternatives:

* Translate the origin of the stage to the center of the screen. And then place all children in that group.

* Create a group that’s positioned at the center on the screen.

[ingemar]

@walter

I guess Option 1 would be OK. If I understand this correctly I’ll then have a true Cartesian coordinate system with (0,0) at the center of the screen, right?

[walter]

Yea.

BTW, your suggestion on the other thread made me wonder if there were a camera concept that could be introduced that would encapsulate this somehow.