WebGLRenderingContext: drawArrays() method
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Note: This feature is available in Web Workers.
The WebGLRenderingContext.drawArrays()
method of the WebGL API renders primitives from array data.
Syntax
js
drawArrays(mode, first, count)
Parameters
mode
-
A
GLenum
specifying the type primitive to render. Possible values are:gl.POINTS
: Draws a single dot.gl.LINE_STRIP
: Draws a straight line to the next vertex.gl.LINE_LOOP
: Draws a straight line to the next vertex, and connects the last vertex back to the first.gl.LINES
: Draws a line between a pair of vertices.gl.TRIANGLE_STRIP
gl.TRIANGLE_FAN
gl.TRIANGLES
: Draws a triangle for a group of three vertices.
Note: If
mode
isPOINTS
,gl_PointSize
may need to be set fordrawArrays
to render, as its value is unknown if not explicitly written. Only some GPUs set its default as1.0
. first
-
A
GLint
specifying the starting index in the array of vector points. count
-
A
GLsizei
specifying the number of indices to be rendered.
Return value
None (undefined
).
Exceptions
- If
mode
is not one of the accepted values, agl.INVALID_ENUM
error is thrown. - If
first
orcount
are negative, agl.INVALID_VALUE
error is thrown. - if
gl.CURRENT_PROGRAM
isnull
, agl.INVALID_OPERATION
error is thrown.
Examples
js
gl.drawArrays(gl.POINTS, 0, 8);
Specifications
Specification |
---|
WebGL Specification # 5.14.11 |
Browser compatibility
BCD tables only load in the browser
See also
WebGLRenderingContext.drawElements()
ext.drawArraysInstancedANGLE()
ext.drawElementsInstancedANGLE()
ext.vertexAttribDivisorANGLE()
WebGL2RenderingContext.drawArraysInstanced()
WebGL2RenderingContext.drawElementsInstanced()
WebGL2RenderingContext.vertexAttribDivisor()
WEBGL_multi_draw.multiDrawArraysWEBGL()