gl_PointSize — contains size of rasterized points, in pixels
gl_PointSize is a member of the
gl_PerVertex named block:
out gl_PerVertex {
highp vec4 gl_Position;
highp float gl_PointSize;
};
In the vertex, tessellation evaluation and geometry languages, a single
global instance of the gl_PerVertex named block is available and
its gl_PointSize member is an output that receives the
intended size of the point to be rasterized, in pixels. It may be written at any time
during shader execution.
In the tessellation control language, the gl_PerVertex named block
is used to construct an array, gl_out[], whose members become
available as inputs to the subsequent tessellation evaluation shader.
The value of gl_PointSize (or the gl_PointSize member of the gl_out[]
array, in the case of the tessellation control shader)
is undefined after the vertex, tessellation control, and tessellation evaluation
shading stages if the corresponding shader executable does
not write to gl_PointSize. It is also undefined after the geometry processing stage if the geometry shader executable calls
EmitVertex without having
written gl_PointSize since the last call to EmitVertex
(or hasn't written it at all).
In the tessellation control, tessellation evaluation and geometry languages,
the gl_PerVertex named block is used to construct an array, gl_in[]
of per-vertex or per-control point inputs whose content represents the corresponding
outputs written by the previous stage.
The variable gl_PointSize is intended for a vertex shader to write
the size of the point to be rasterized. It is measured in pixels.
If gl_PointSize is not written to, its value is undefined in subsequent
pipeline stages. If the last active stage is not a vertex shader and does not statically assign a
value to gl_PointSize , the point size is 1.0.
| OpenGL ES Shading Language Version | ||||
|---|---|---|---|---|
| Variable Name | 1.00 | 3.00 | 3.10 | 3.20 |
| gl_PointSize | ✔ | ✔ | ✔ | ✔ |
| gl_PointSize (geometry shader) | - | - | - | ✔ |
| gl_PointSize (tessellation evaluation shader) | - | - | - | ✔ |
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