Canvas troubleshooting: Difference between revisions

== Useful C++ changes ==

{{Note|The following patches are intended to help better understand what's going on behind the scenes. They are intended to be regularly rebased onto SG/FG 'next'. In the mid-term, our hope is to ensure that people working on Nasal/Canvas related features get a better understanding about when, where and why performance is affected.}}

=== Tracking update frequency per Canvas/Element ===

This is intended to help people better understand how frequently a Canvas is being updated, which happens automatically once a property in the sub-tree is modified (usually involving timers and listeners):

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The following patch is intended to help determine the rendering overhead of Canvas by adding optional draw-masks for disabling rendering of Canvas textures via their corresponding placements (aircraft, scenery and GUI):

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Under the hood, the corresponding Nasal/C++ code updating Canvas textures would obviously still be running - it would just be rendering that is explicitly disabled here.

=== Hooking up Canvas to the Osg Stats ===

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Once a complex Canvas texture (MFD) has been set up, the following patch can be used for invoking osgUtil::Optimizer() to finalize and optimize the scene graph:

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=== Tracking RAM utilization per Canvas ===

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=== Tracking update/cull and draw per Canvas or Element ===

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With Canvas textures typically not rendering any scene/scenery data (terrain), we don't necessarily need those Cameras to render within the main viewer. This is intended to help better leverage OSG-level concurrency support by using a separate CompositeViewer instance to render Canvas textures, without having to change the main OSGViewer and its threading mode:

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