This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The WebGL2RenderingContext.drawArraysInstanced() method of the WebGL 2 API renders primitives from array data like the gl.drawArrays() method. In addition, it can execute multiple instances of the range of elements.
Note: When using WebGL 1, the ANGLE_instanced_arrays extension can provide this method, too.
Syntax
void gl.drawArraysInstanced(mode, first, count, instanceCount);
Parameters
mode- A
GLenumspecifying 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_STRIPgl.TRIANGLE_FANgl.TRIANGLES: Draws a triangle for a group of three vertices.
- first
- A
GLintspecifying the starting index in the array of vector points. - count
- A
GLsizeispecifying the number of indices to be rendered. - instanceCount
- A
GLsizeispecifying the number of instances of the range of elements to execute.
Return value
None.
Examples
gl.drawArraysInstanced(gl.POINTS, 0, 8, 4);
Specifications
| Specification | Status | Comment |
|---|---|---|
| WebGL 2.0 The definition of 'drawArraysInstanced' in that specification. |
Editor's Draft | Initial definition for WebGL. |
| OpenGL ES 3.0 The definition of 'glDrawArraysInstanced' in that specification. |
Standard | Man page of the (similar) OpenGL API. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | No support [2] | Nightly build [1] | No support | No support | No support |
| Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|
| Basic support | No support | No support | No support | No support | No support | No support |
[1] WebGL 2 is enabled by default in Firefox Nightly. To enable it in a release version of Firefox, set the preference webgl.enable-prototype-webgl2 to true in about:config.
[2] To use an experimental implementation of WebGL 2 in Chrome, you have to start Chrome with the runtime flag --enable-unsafe-es3-apis.