Blue offers a number of ways to render a project, each method useful for different purposes you may have. The following section explains the ways which Blue is able to render a .blue project file as well as possible use-case scenarios to guide you on how that feature may be useful.
Render in Real-time
Rendering in uses the project's Real-Time render settings to render the project in realtime to the users soundcard. This is the most common rendering one will likely use. To use this, you can press the play button at the top of the window, use the "Project->Render/Stop Project" menu option, or use the F9 shortcut key.
Generate CSD to Screen
Blue's general method of communicating with Csound is by generating a CSD file and calling Csound to run it. For debugging purposes, it is often useful to see if what you think you are doing inside Blue is matching the generated CSD file. You can generate the CSD to screen by using the "Project->Generate CSD to Screen" menu option, or by using the ctrl-shift-g shortcut.
Generate CSD to Disk
If you'd like to generate a CSD from the current project to a file, you can do so by using the "Project->Generate CSD to File" menu option, or by using the ctrl-g shortcut.
Render to Disk
The Render to Disk option will use the project's Disk Render Options from its project properties to generate a soundfile on disk (format of file depends on how user configures commandline options). I've found this useful for rendering a wav to disk and converting to MP3 to listen to on the go so I can review my current work. To render to disk, you can do so by using the "File->Render to Disk" menu option or use the ctrl-shift-F9 shortcut.
Render to Disk and Play
The Render to Disk and play option will use the project's Disk Render Options from its project properties to generate a soundfile on disk and after finishing, play the generated file using Blue's soundfile player, located in the SoundFile manager tab. This feature is useful if you're working on a piece that has processing demands beyond what your computer is capable of in realtime, so you can have it render to disk first and then play, which will give very smooth playback. It is also useful if you render in realtime with lower quality settings but use higher quality settings for final project output, as you can occasionally test what the output would be like using this feature. To use this option, you can use the "File->Render to Disk and Play" menu option or use the ctrl-F9 shortcut.
Render to Disk and Open
The Render to Disk and Open option will use the project's Disk Render Options from its project properties to generate a soundfile on disk and after finishing, open the generated file using the configured command with the program options. This command may differ from the external command to use with "Render to Disk and Play". To use this option, you can use the "File->Render to Disk and Open" menu option.