WEBGL_multi_draw: multiDrawArraysInstancedWEBGL() method
The WEBGL_multi_draw.multiDrawArraysInstancedWEBGL()
method of the
WebGL API renders multiple primitives from
array data. It is
identical to multiple calls to the
gl.drawArraysInstanced()
method.
Syntax
multiDrawArraysInstancedWEBGL(mode,
firstsList, firstsOffset,
countsList, countsOffset,
instanceCountsList, instanceCountsOffset,
drawCount);
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.
firstsList
-
An
Int32Array
orArray
(ofGLint
) specifying a list of starting indices for the arrays of vector points. firstsOffset
-
A
GLuint
defining the starting point into thefirstsLists
array. countsList
-
An
Int32Array
orArray
(ofGLsizei
) specifying a list of numbers of indices to be rendered. countsOffset
-
A
GLuint
defining the starting point into thecountsList
array. instanceCountsList
-
An
Int32Array
orArray
(ofGLsizei
) specifying a list of numbers of instances of the range of elements to execute. instanceCountsOffset
-
A
GLuint
defining the starting point into theinstanceCountsList
array. drawCount
-
A
GLsizei
specifying the number of instances of the range of elements to execute.
Return value
None.
Exceptions
-
If
mode
is not one of the accepted values, agl.INVALID_ENUM
error is thrown. -
If
drawCount
or items infirstsList
,countsList
, orinstanceCountsList
are negative, agl.INVALID_VALUE
error is thrown. -
if
gl.CURRENT_PROGRAM
isnull
, agl.INVALID_OPERATION
error is thrown.
Examples
const firsts = new Int32Array(/* … */);
const counts = new Int32Array(/* … */);
const instanceCounts = new Int32Array(/* … */);
ext.multiDrawArraysInstancedWEBGL(
gl.TRIANGLES,
firsts,
0,
counts,
0,
instanceCounts,
0,
firsts.length,
);
Specifications
Specification |
---|
WebGL WEBGL_multi_draw Extension Specification |
Browser compatibility
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