App Stats

We can view app-related stats by accessing the Context.stats property. By default, this tracks the app run time, the last delta time, the total rendered frames, the current fps (averaged over the last 25 frames), and OpenGL-related stats referred to as engine stats.

Engine Stats

Engine stats tracks OpenGL related stats. This is enabled by default. The list of stats tracked are as follows:

• bufferAllocations: All the buffer allocations and their size.
• totalBufferSize: The total size of all buffers
• shaderSwitches: The total times shaders have been switched in the last call
• vertices: the total vertices being rendered
• textureBindings: the total textures bound
• drawCalls: the total amount of draw related calls invoked
• calls: the total OpenGL related calls invoked

Outputting Stats to the Console

Fortunately, we don’t have to worry about formatting all these stats to render to the console. By default, AppStats.toString() handles this formatting already. All we have to do is just add it to our logger message and it will output in a nicely formatted way.

onRender { dt ->
    if (input.isKeyJustPressed(Key.P)) {
        logger.info { stats }
    }
}

[12:18:49.778] - [Thread: 1] - [JVM - UI Test]:
***************** APP STATS *****************
FPS (last 25 frames): 115.4
Run time: 2s
GL calls: 83
Draw calls: 3
Vertices: 186
Textures: 3
Shaders: 2
Buffers: 4 with memory usage of 1.6M

****************** END APP STATS *************

Process finished with exit code 0