TBGL- multiple displays

[ReneMiner]

More than one TBGL-display quite easy to achieve - but needs UI-Canvas.

Example shows how two different "scenes" can be displayed in two different canvas-controls at same time.
Not using scene/entity-system here but is doable rendering different scenes to different output also.
Even works in seperate dialogs.
If displaying same scene from different points of view then camera-entity has to be placed according to the current view.



Uses "UI", "TBGL"

' -- ID numbers of controls
Begin ControlID
%lCanvas1
%lCanvas2

%bClose

%myTimer
End ControlID

Begin Const
%MAIN_WIDTH = 640
%MAIN_HEIGHT = 480

%timeOut = 20 ' -- Determines graphics refresh rate in milliseconds
End Const

Function TBMain()

Local hDlg As DWord

Dialog New Pixels, 0, "Dialog with TBGL",-1,-1, %MAIN_WIDTH, %MAIN_HEIGHT, _
%WS_POPUP Or %WS_VISIBLE Or _
%WS_CLIPCHILDREN Or %WS_CAPTION Or _
%WS_SYSMENU Or %WS_MINIMIZEBOX Or %WS_MAXIMIZEBOX, 0 To hDlg

' -- Place controls:
Control Add Label, hDlg, %lCanvas1, "", 5, 5, %MAIN_WIDTH/2-10, %MAIN_HEIGHT-40
Control Set Color hDlg, %lCanvas1, %BLACK, %BLACK

Control Add Label, hDlg, %lCanvas2, "", %Main_Width/2+5, 5, %MAIN_WIDTH/2-10, %MAIN_HEIGHT-40
Control Set Color hDlg, %lCanvas2, %BLACK, %BLACK

Control Add Button, hDlg, %bClose, "Close", 5, %MAIN_HEIGHT-30, %MAIN_WIDTH - 10, 25

Dialog Show Modal hDlg, Call dlgCallback

End Function

CallBack Function dlgCallback()
Static hCtrl As DWord

Select Case CBMSG

Case %WM_INITDIALOG
' just init timer
Dialog Set Timer CBHNDL, %myTimer, %timeOut, %NULL

Case %WM_TIMER
Control Handle CBHNDL, %lCanvas1 To hCtrl
RenderMyImage(hCtrl, %lCanvas1)

Control Handle CBHNDL, %lCanvas2 To hCtrl
RenderMyImage(hCtrl, %lCanvas2)

Case %WM_CLOSE
Control Handle CBHNDL, %lCanvas1 To hCtrl
If TBGL_CanvasBound(hCtrl) Then TBGL_ReleaseCanvas(hCtrl)
Control Handle CBHNDL, %lCanvas2 To hCtrl
If TBGL_CanvasBound(hCtrl) Then TBGL_ReleaseCanvas(hCtrl)

Dialog Kill Timer CBHNDL, %myTimer

Case %WM_COMMAND
Select Case CBCTL

Case %bClose
If CBCTLMSG = %BN_CLICKED Then Dialog End CBHNDL

End Select

End Select
End Function


Sub RenderMyImage( ByVal hCtrl As DWord, ByVal ID_Canvas As Long )


TBGL_BindCanvas(hCtrl) ' no need to update canvas-proprtions...

If TBGL_CanvasBound(hCtrl) Then

TBGL_UseLighting(%TRUE)
TBGL_UseLightSource(%GL_LIGHT0, %TRUE)
TBGL_SetLightParameter(%GL_LIGHT0, %TBGL_LIGHT_POSITION, 15, 10, 15, 1)


TBGL_ClearFrame
TBGL_Camera(5, 5, 5, 0, 0, 0)

If ID_Canvas = %lCanvas1 Then
' show "scene 1"
TBGL_Box(1, 1, 1)
Else
' show "scene 2"
TBGL_Sphere(1)
EndIf

TBGL_DrawFrame

EndIf
End Sub


Edit: limitation removed

[Petr Schreiber]

I will check during the weekend whether I can work around this limitation.


Petr

[Petr Schreiber]

Hmm,

I don't see any problem changing LOC and SIZE property, could you please post failing example?


Petr

[ReneMiner]

I threw it all out and have not saved the "old" version.

Maybe I did it wrong? The effect was the canvases did not correctly resize (used CONTROL SET RESIZE) and without that switch I did not try out. Maybe this switch interfered also when I used CONTROL SET LOC.

That's also the reason why I tried to create multiple TBGL-displays at all: As long as Dialogs & Controls are not Objects with clearly defined Events, Methods and Properties they are way too cumbersome to handle and not applicable for a bigger project so I need to create own "Control-Objects"
I already was that frustrated about UI-handling that I erased all I've written - and more than once - lots of hours thinking and typing just flushed down to neverland.
Especially annoying that I can not use Dialogs nor Control-Properties directly, but always have to send them "TO" some local variable in advance with half a dozen parameters just to get some simple value out there and need always a few lines just for one simple action because the result is not returned directly.
Also these make code so unreadable - I have some idea, start to write and get stuck when it comes to UI - always have to look up and down again - my code then is such chaos that I can not read myself what I wrote and loose overview of situation and used calls so it becomes impossible to continue and I have to stop and start all over.

[Petr Schreiber]

Hi Rene,

I think CONTROL SET RESIZE could clash a bit with CONTROL SET LOC/SIZE - it is one or another.
I agree the "TO syntax" is a bit impractical sometimes -that is why Eros added Control_GetHandle, Control_GetWidth, Control_GetHeight, Control_GetText and others... which behave like normal functions.


Petr