Screen usage flag types

Types of usage flags.

Synopsis:

#include <screen/screen.h>

 enum {
      SCREEN_USAGE_READ = (1 << 1)   
      SCREEN_USAGE_WRITE = (1 << 2)   
      SCREEN_USAGE_NATIVE = (1 << 3)   
      SCREEN_USAGE_OPENGL_ES1 = (1 << 4)   
      SCREEN_USAGE_OPENGL_ES2 = (1 << 5)   
      SCREEN_USAGE_OPENGL_ES3 = (1 << 11)   
      SCREEN_USAGE_OPENVG = (1 << 6)   
      SCREEN_USAGE_VIDEO = (1 << 7)   
      SCREEN_USAGE_CAPTURE = (1 << 8)   
      SCREEN_USAGE_ROTATION = (1 << 9)   
      SCREEN_USAGE_OVERLAY = (1 << 10)   
};

Data:

SCREEN_USAGE_READ: Flag to indicate that buffer(s) associated with the API object can be read from.

SCREEN_USAGE_WRITE: Flag to indicate that buffer(s) associated with the API object can be written to.

SCREEN_USAGE_NATIVE: Flag to indicate that buffer(s) associated with the API object can be used for native API operations.; If using blits or fills, this flag must be set on the API object.

SCREEN_USAGE_OPENGL_ES1: Flag to indicate that OpenGL ES 1.X is used for rendering the buffer associated with the API object.

SCREEN_USAGE_OPENGL_ES2: Flag to indicate that OpenGL ES 2.X is used for rendering the buffer associated with the API object.

SCREEN_USAGE_OPENGL_ES3: Flag to indicate that OpenGL ES 3.X is used for rendering the buffer associated with the API object.

SCREEN_USAGE_OPENVG: Flag to indicate that OpenVG is used for rendering the buffer associated with the API object.

SCREEN_USAGE_VIDEO: Flag to indicate that the buffer can be written to by a video decoder.

SCREEN_USAGE_CAPTURE: Flag to indicate that the buffer can be written to by capture devices (such as cameras, analog-to-digital-converters, ...), and read by a hardware video encoder.

SCREEN_USAGE_ROTATION: Flag to indicate that the buffer can be re-configured from landscape to portrait orientation without reallocation.; Rotation

SCREEN_USAGE_OVERLAY: Flag to indicate the use of a non-composited layer.; The Screen API uses a composited layer by default. The SCREEN_USAGE_OVERLAY flag is used to override this default behaviour to use a non-composited layer instead. Note that when the overlay usage bit is added or removed, then changing SCREEN_USAGE_OVERLAY affects the pipeline. Set this SCREEN_USAGE_OVERLAY flag when you are targeting a non-composited pipeline.

Library:

libscreen

Description:

Usage flags are used when allocating buffers. Depending on the usage, different constraints such as width, height, stride granularity or special alignment must be observed. The usage is also valuable in determining the amount of caching that can be set on a particular buffer.