Runtime configuration

In this section, we will cover some of the runtime configuration options that you can use to customize the behavior of the runtime.

Android properties

If you are using JSAR in YodaOS-Master or other AOSP-based systems, you can use these properties to configure the runtime.

Entering the debugging mode

Before all the configration, you need to enable the debugging mode:

adb shell setprop jsar.debug.enabled yes

Disable the caching

To disable the resource caching:

adb shell setprop jsar.resources.caching no

Enable the renderer tracing

To enable the tracing of the renderer:

adb shell setprop jsar.renderer.tracing yes

Then you can view the logs in TR_GLES channel:

07-18 17:49:16.204 TR_GLES: [0] GL::ActiveTexture(0)
07-18 17:49:16.204 TR_GLES: [0] GL::BindTexture(0xde1, 24) for active(33984) program(24)
07-18 17:49:16.204 TR_GLES: [0] GL::ActiveTexture(1)
07-18 17:49:16.204 TR_GLES: [0] GL::BindTexture(0xde1, 3) for active(33985) program(24)
07-18 17:49:16.204 TR_GLES: [0] GL::DrawElements(mode=GL_TRIANGLES, count=5220, type=GL_UNSIGNED_INT, indices=0x0)
07-18 17:49:16.204 TR_GLES:     Program: 24
07-18 17:49:16.204 TR_GLES:     Program: LINK_STATUS=1
07-18 17:49:16.204 TR_GLES:     Program: VALIDATE_STATUS=0
07-18 17:49:16.204 TR_GLES:     Element Array Buffer: 92
07-18 17:49:16.204 TR_GLES:     Active Attribute(0): Enabled=Yes Size=1 Type=0x8b51 "normal"
07-18 17:49:16.204 TR_GLES:     Active Attribute(1): Enabled=Yes Size=1 Type=0x8b50 "uv"
07-18 17:49:16.204 TR_GLES:     Active Attribute(2): Enabled=Yes Size=1 Type=0x8b52 "matricesWeights"
07-18 17:49:16.204 TR_GLES:     Active Attribute(3): Enabled=Yes Size=1 Type=0x8b51 "position"
07-18 17:49:16.204 TR_GLES:     Active Attribute(4): Enabled=Yes Size=1 Type=0x8b52 "matricesIndices"

Enable graphics debugging

To enable the graphics debugging:

adb shell setprop jsar.renderer.graphics.debug yes

Then you can view the graphics debugging logs in TR_GLES channel as well:

07-18 17:49:16.204 TR_GLES: [KHR_debug] GL::DebugMessageCallback(0x0, 0x0, 0x0, 0x0)

This option is only available in the OpenGLES backend and requires the support of the KHR_debug extension in the device.

Configure click distance threshold

Click Distance Threshold

The click distance threshold determines the maximum distance between mousedown and mouseup hit points for triggering click events, as defined in the Web UI Events specification. This threshold helps distinguish between click and drag gestures by measuring the spatial proximity of pointer events.

When a user interaction begins with a selectStart event and ends with a selectEnd event, a click event is only generated if:

1. Both events target the same element
2. The distance between hit points is less than the configured threshold

Configuration

To configure the click distance threshold:

adb shell setprop jsar.events.click_distance_threshold 5

The default value is 5 pixels, which provides good tolerance for pointer device jitter while maintaining distinction between click and drag gestures.

• Smaller values (1-3): More precise click detection, may be harder to trigger clicks with pointing devices
• Larger values (5-10): More tolerant of device jitter, easier to trigger clicks but may register drags as clicks

You can also set this via environment variable at non-Android platforms:

export JSAR_CLICK_DISTANCE_THRESHOLD=5