为什么我收到这个错误 "WebGL: INVALID_OPERATION: drawArrays: front and back stencils settings do not match"

Question

我的代码如下。错误行是最后一行。

  gl.enable(gl.STENCIL_TEST);
  gl.stencilFuncSeparate(gl.FRONT, gl.ALWAYS, 1, 0xFF);
  gl.stencilOpSeparate(gl.FRONT, gl.KEEP, gl.KEEP, gl.REPLACE);
  gl.stencilMaskSeparate(gl.FRONT, 0xFF);
  gl.clear(gl.STENCIL_BUFFER_BIT);

  gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);//error line

Answer 1

来自the WebGL spec

6.10 Stencil Separate Mask and Reference Value

In the WebGL API it is illegal to specify a different mask or reference value for front facing and back facing triangles in stencil operations. A call to drawArrays or drawElements will generate an INVALID_OPERATION error if:

STENCIL_WRITEMASK != STENCIL_BACK_WRITEMASK (as specified by stencilMaskSeparate for the mask parameter associated with the FRONT and BACK values of face, respectively)

STENCIL_VALUE_MASK != STENCIL_BACK_VALUE_MASK (as specified by stencilFuncSeparate for the mask parameter associated with the FRONT and BACK values of face, respectively)

STENCIL_REF != STENCIL_BACK_REF (as specified by stencilFuncSeparate for the ref parameter associated with the FRONT and BACK values of face, respectively)

我猜 it's a DirectX limit 必须添加 WebGL 才能在 DirectX运行中使用

为什么我收到这个错误 "WebGL: INVALID_OPERATION: drawArrays: front and back stencils settings do not match"

why i got this error "WebGL: INVALID_OPERATION: drawArrays: front and back stencils settings do not match"

opengl-es

webgl

6.10 Stencil Separate Mask and Reference Value