axmol/core/renderer/backend/opengl/DepthStencilStateGL.cpp

/****************************************************************************
 Copyright (c) 2018-2019 Xiamen Yaji Software Co., Ltd.

 https://axis-project.github.io/

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 of this software and associated documentation files (the "Software"), to deal
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 all copies or substantial portions of the Software.

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 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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 THE SOFTWARE.
 ****************************************************************************/

#include "DepthStencilStateGL.h"
#include "platform/CCGL.h"

#include "renderer/backend/opengl/MacrosGL.h"
#include "renderer/backend/opengl/UtilsGL.h"

NS_AX_BACKEND_BEGIN

void DepthStencilStateGL::reset()
{
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_STENCIL_TEST);
}

void DepthStencilStateGL::apply(unsigned int stencilReferenceValueFront, unsigned int stencilReferenceValueBack) const
{
    const auto dsFlags = _depthStencilInfo.flags;
    // depth test
    if (bitmask::any(dsFlags, DepthStencilFlags::DEPTH_TEST))
    {
        glEnable(GL_DEPTH_TEST);
    }
    else
    {
        glDisable(GL_DEPTH_TEST);
    }

    if (bitmask::any(dsFlags, DepthStencilFlags::DEPTH_WRITE))
        glDepthMask(GL_TRUE);
    else
        glDepthMask(GL_FALSE);

    glDepthFunc(UtilsGL::toGLComareFunction(_depthStencilInfo.depthCompareFunction));

    // stencil test
    if (bitmask::any(dsFlags, DepthStencilFlags::STENCIL_TEST))
    {
        glEnable(GL_STENCIL_TEST);

        if (_isBackFrontStencilEqual)
        {
            glStencilFunc(UtilsGL::toGLComareFunction(_depthStencilInfo.frontFaceStencil.stencilCompareFunction),
                          stencilReferenceValueFront, _depthStencilInfo.frontFaceStencil.readMask);
            glStencilOp(UtilsGL::toGLStencilOperation(_depthStencilInfo.frontFaceStencil.stencilFailureOperation),
                        UtilsGL::toGLStencilOperation(_depthStencilInfo.frontFaceStencil.depthFailureOperation),
                        UtilsGL::toGLStencilOperation(_depthStencilInfo.frontFaceStencil.depthStencilPassOperation));
            glStencilMask(_depthStencilInfo.frontFaceStencil.writeMask);
        }
        else
        {
            glStencilFuncSeparate(GL_BACK,
                                  UtilsGL::toGLComareFunction(_depthStencilInfo.backFaceStencil.stencilCompareFunction),
                                  stencilReferenceValueBack, _depthStencilInfo.backFaceStencil.readMask);
            glStencilFuncSeparate(
                GL_FRONT, UtilsGL::toGLComareFunction(_depthStencilInfo.frontFaceStencil.stencilCompareFunction),
                stencilReferenceValueFront, _depthStencilInfo.frontFaceStencil.readMask);

            glStencilOpSeparate(
                GL_BACK, UtilsGL::toGLStencilOperation(_depthStencilInfo.backFaceStencil.stencilFailureOperation),
                UtilsGL::toGLStencilOperation(_depthStencilInfo.backFaceStencil.depthFailureOperation),
                UtilsGL::toGLStencilOperation(_depthStencilInfo.backFaceStencil.depthStencilPassOperation));
            glStencilOpSeparate(
                GL_FRONT, UtilsGL::toGLStencilOperation(_depthStencilInfo.frontFaceStencil.stencilFailureOperation),
                UtilsGL::toGLStencilOperation(_depthStencilInfo.frontFaceStencil.depthFailureOperation),
                UtilsGL::toGLStencilOperation(_depthStencilInfo.frontFaceStencil.depthStencilPassOperation));

            glStencilMaskSeparate(GL_BACK, _depthStencilInfo.backFaceStencil.writeMask);
            glStencilMaskSeparate(GL_FRONT, _depthStencilInfo.frontFaceStencil.writeMask);
        }
    }
    else
        glDisable(GL_STENCIL_TEST);

    CHECK_GL_ERROR_DEBUG();
}

NS_AX_BACKEND_END