Rendering an OpenGL playblast of the animation

Playblast is a term used by a famous commercial package to indicate the preview of the animation in true speed; although I've heard only very few people using it in relation to Blender, I thought it might be a good way to indicate the fast OpenGL preview rendering obtained for checking the animated action.

Start Blender and load the Gidiosaurus_lighting.blend file.

Here are the steps to begin with the OpenGL rendering:

In our example, the OpenGL playblast rendered single .png images with an alpha background because, as you can see in the Render window visible in the previous screenshot, these are the settings of the Output subpanel. Be aware that the resolution, the format and the path where the playblast frames are saved, always depend on the settings in the Render window, the same settings that will be used for the final real rendering (but of course the resolution of the playblast can be easily and temporarily be made smaller with the slider of the percentage scale).

Once we have rendered all the frames, we can use an external player to see them in sequence (in Ubuntu, I use the free player DJV Imaging, http://djv.sourceforge.net) or, just quickly build a movie through the Blender Sequencer:

  1. Go to the Screen datablock button on the top main header and click it to switch to the Video Editing screen:
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    Switching to the Video Editing screen layout

  2. Put the mouse pointer in the Video Sequence Editor window at the bottom and press Shift + A; from the pop-up menu select the Image item (Add an image or image sequence to the sequencer), then browse to the playblast folder location, click on it and once inside, press the A key to select all the contained frames, then press Enter to confirm. The frames are added to the Video Sequence Editor window as a single strip and the current frame appears in the preview window:
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    Loading the rendered frames in the Video Sequence Editor

  3. Go back to the Default screen and to the Render window under the main Properties panel. In the Output subpanel, where you can change the path to save the movie in a different location (or also leave it as it is), click on the File Format button to select a Movie format, for example, AVI JPEG. Choose BW or RGB and the Quality compression ratio (but the default 90% is usually OK); then go to the Post Processing subpanel and ensure that the Sequencer item is enabled:
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    The Output and the Post Processing subpanels inside the Render window

  4. Go to the top of the Render window and click on the Animation button; remember that Blender uses two different buttons to start the rendering of a still image or of an animation, both for the final rendering and for the 3D viewport toolbar OpenGL preview we have seen in the How to do it… section.

The rendering starts and the Sequencer processes all the .png images outputted by the playblast, transforming them into a single compressed .avi movie then saved in the same directory as the frames.

The process is visible in the UV/Image Editor window that replaced the Camera view, indicated in the toolbar by the Render Result label on the image datablock to the left (because the Image Editor item is the one selected in the Display slot under the Render subpanel) and by the Sequence label visible in the Layer slot to the right: