Canvas issues

This article is a stub. You can help the wiki by expanding it.

Canvas - the FlightGear 2D drawing API
Canvas - Main Page Canvas News - for the latest developments Shiva Alternatives - ongoing work for Core Profile support Canvas Efforts - projects using the Canvas system Canvas FAQs - frequently asked questions Canvas - Getting started Canvas Development (core) Canvas Troubleshooting (core) Canvas Sandbox (core) PUI2Canvas (PUI/XML Parser) Canvas GUI Canvas Widgets Canvas Maps Canvas Snippets
RFC
Canvas Instancing Howto:New Canvas Execution Model Canvas SVG Canvas Popout Windows Canvas Scenery Overlays
Frameworks
Canvas Map API (soon deprecated!) Canvas MapStructure Canvas MapStructure Layers MapStructure Snippets Canvas Radar Canvas Animation Framework (WIP) Canvas Plotting Framework (WIP) Canvas MFD Framework Canvas ND Framework Canvas PFD Framework Canvas MCDU Framework Canvas EFB Framework Canvas Wrappers Canvas Glass Cockpit Efforts
Tutorials
Howto:Getting started with Canvas Howto: Canvas Troubleshooting Howto:Adding a canvas to a GUI dialog (PUI!) Howto:Creating a Canvas GUI dialog file (New) Howto:Dynamic Liveries via Canvas (new) Howto:Creating a Canvas GUI Widget Howto:Add a 2D canvas instrument to your aircraft Howto:Parsing 2D Instruments using the Canvas Howto:Creating fullscreen Canvas applications Howto:Use SVG inside a Canvas Howto:Extend the Canvas SVG module Howto:Serializing a Canvas to SVG Howto:Canvas applications as Nasal submodules Howto:Using raster images and nested canvases Canvas HUD Howto:Project 3D to 2D coordinates on desktop canvas
Reference
Canvas Element Group Image Map Path Text Canvas Nasal API MessageBox Layout System Canvas GUI API Canvas draw library Event Handling
Related
Canvas Properties Unifying the 2D rendering backend via canvas Howto:Use a Camera View in an Instrument Howto:Extending Canvas to support rendering 3D models Howto:Extending Canvas to support MathGL
To be ported
Navigation display Map FGCanvas Canvas Nasal/JavaScript Subset
Deprecated by Canvas
Complex Glass Cockpit Avionics
(click on headings to toggle)

Critical / Bugs

White Square / No FBO

Regarding the Canvas related issues you are mentioning, those would seem to suggest that your GPU/driver is lacking support for features required for Canvas - which is exactly why we're asking people to provide complete bug reports, including their GPU make/model and OS/driver etc (see the red box at the top of the support forum)

The white square is the popup message / tooltip, shown via the Canvas. The texture or framebuffer used for the canvas isn't working. This seems to happen on some very old drivers.

For example, reported on Intel GMA 3100, Intel G33/G31 Express Chipset Family

on an old Intel graphics netbook, and while FG obviously doesn't work very well, some of the osg RTT demos actually DO work correctly. Besides, osgviewer itself, and even fgviewer, work well enough, with acceptable framerates/performance - so it would seem possible to optimie things a bit to also support such hardware.

if in doubt, post more screenshots detailing exactly what you are doing, or even post a youtube video illustrating the problem

please post your hardware specs as per the box at the top of the forum.

It seems that you are lacking some OpenGL support that is required by the new canvas system.

This has been recently reported at least once: viewtopic.php?f=68&t=20887&hilit=canvas+fbo

So please follow up with your exact hardware/software specs, including info from the HELP/ABOUT dialog.

And if you are affected by this, please consider filing a bug report so that we can look into it: http://flightgear-bugs.googlecode.com/

we talked about this issue a (long) while ago - and what would really be interesting is if people seeing this could also try one of the aircraft using other OD_gauge based avionics (navdisplay, agradar, wxradar etc) - because under the hood, this should be using the same OSG code - if those instruments work/display properly, it is likely that this issue can be fixed once and for all by looking at what the Canvas FBO/RTT setup code is doing differently compared to od_gauge based avionics using the same back-end. If I remember correctly, we also once posted patches telling OSG to use a non-FBO fallback - unfortunately nobody seeing this issue was able to follow up to test this. If in doubt, anybody seeing this, PLEASE post a screenshot showing your help/about dialog (and ideally your fgfs.log file): About dialog

Commonly used debugging tools#fgfs.log

Likewise, this should affect any other FBO use-cases in FlightGear, including multi-camera setups (think Rembrandt)

could the people getting "white canvases" please get in touch to test a patch ?

Basically, the idea is to check if FBO setup failed and try some more conservative alternatives like pbuffers or ARBs instead.

We can use PIXEL_BUFFER_RTT or PIXEL_BUFFER instead of FRAME_BUFFER_OBJECT: http://lists.openscenegraph.org/pipermail/osg-users-openscenegraph.org/2007-November/004790.html Given that we're going to use Canvas in more and more placed, including the GUI, it would seem like a good idea to get this sorted obviously.

On the other hand, it is hard to troubleshoot this without being affected by the problem yourself :-) it's not a new problem: http://www.mail-archive.com/flightgear-devel%40lists.sourceforge.net/msg20103.html

References

References