gles2-maze

Updated: April 19, 2023

Demonstrate how to use texture, as well as vertex and fragment shaders

Syntax:

gles2-maze [-bg-alpha=background_alpha_value]
           [-config=egl_configuration] 
           [-display=display_id]
           [-fg-alpha=foreground_alpha_value]     
           [-frame-limit=frames]
           [-interval=swap_interval]
           [-nbuffers=count]
           [-pipeline=pipeline_id]     
           [-pos=x,y]
           [-size=widthxheight]
           [-transparency=transparency_mode]
           [-verbose]
           [-zorder=zorder]

Runs on:

QNX Neutrino

Options:

-bg-alpha=background_alpha_value

Set the background to the specified alpha value as a float in the range [0.0f..1.0f]. If you don't specify the bg-alpha option, gles2-maze uses 0.0f.

-config=egl_configuration

Set optional EGL configuration specifiers. These optional configuration specifiers are set using a comma-separated list. The specifiers may include the following: pixel format and/or multi-sampling specifications, or an EGL configuration number. If you're using an EGL configuration number, it must not be specified with other specifiers.

Pixel format

Specify pixel format as one of the following:

  • rgba1010102 or rgbx1010102
  • bgra1010102 or bgrx1010102
  • rgba8888 or rgbx8888
  • bgra8888 or bgrx8888
  • rgba5551 or rgbx5551
  • rgba4444 or rgbx4444
  • rgb565

where "a" indicates alpha bits and "x" indicates that the alpha bits are ignored.

Sampling

Specify multi-sampling as:

[rate]x

where rate is a valid sampling rate (e.g., 2, 4, 8, ...).

EGL configuration number
Specify as an integer. The integer must be a valid EGL configuration ID (EGL_CONFIG_ID).

For example, the following are all valid ways of specifying the EGL configuation option:

  • -config=rgb565
  • -config=rgba8888,4x
  • -config=12

If no specific EGL configuration is provided, this utility uses the platform-specific EGL configuration. Use egl-configs to determine the the EGL configurations that are supported on your target.

-display=display_id
Show the events on the display as specified by display_id. You can specify display_id as one of the following:
  • an integer that identifies the display
  • a string that identifies the connection type to the display; acceptable strings are:
    • internal
    • composite
    • svideo
    • YPbPr
    • rgb
    • rgbhv
    • dvi
    • hdmi
    • other
Whether by integer or by string, the display that you specify using display_id must be one of the displays that you've configured in the display subsections of the winmgr section in your configuration file (e.g., graphics.conf). If the requested display is not found, gles2-maze will exit with an error.

If you don't have any display subsections configured, or if you don't specify the display option, gles2-maze uses the default display.

-fg-alpha=foreground_alpha_value

Set the foreground to the specified alpha value as a float in the range [0.0f..1.0f]. If you don't specify the fg-alpha option, gles2-maze uses 1.0f.

-frame-limit=frames
Limit the number of frames rendered to the value specified by frame_limit (integer); after the frame limit is reached, gles2-maze exits. By default, this utility assumes an unlimited number of frames (-1).
-interval=swap_interval
Set the swap interval, as an integer (default is 1). The swap interval is the minimum number of vsync periods between image updates.
-nbuffers=count
Set the number of window buffers to be created for rendering. The default is 2.
-pipeline=pipeline_id
Set the pipeline as specified by pipeline_id (integer). If you don't specify this option, gles2-maze uses the pipeline of the framebuffer.

If you use this option, Screen applies the SCREEN_USAGE_OVERLAY usage flag and uses the pipeline specified by pipeline_id.

-pos=x,y
Sets the x,y coordinates of the viewport. The default coordinate of 0,0 is used if this option isn't specified.
-size=widthxheight
Set the size as specified, using integer values for width and height, of the viewport. The default size is fullscreen.
-transparency=transparency_mode
Set the transparency mode of the window. Valid transparency modes are:
Transparency mode Description
none Default mode; result is an opaque window
test Destination pixels are replaced by source pixels; pixels may be opaque or fully transparent
src Destination pixels are replaced by source pixels, including the alpha channel; window will be blended with contents underneath it
-verbose
Print information to display.
-zorder=zorder
Set the z-order specified by zorder, as an integer, of the window. A z-order of 0 is used if this option isn't specified.

Description:

The gles2-maze binary is a command-line tool that can be used to confirm that screen is running, and that all necessary drivers for OpenGL ES 2.x are in place, and can start successfully.

To invoke gles2-maze:

  1. Ensure that screen is running.
  2. Run gles2-maze from either your startup script or from a shell.

Examples:

# gles2-maze