Fix reference context when clearing empty area.

Reference context clear*() calls were crashing on assert when target rectangle
width or height was zero after applying scissor and viewport. Reference context
now skips clears when target area size is zero.

Bug: 19695755
Change-Id: I10e98fbbb8db0e099c039ecd583d6f5bb81af626

diff --git a/framework/opengl/simplereference/sglrReferenceContext.cpp b/framework/opengl/simplereference/sglrReferenceContext.cpp
index 1bead80..57a10c7 100644 (file)
--- a/framework/opengl/simplereference/sglrReferenceContext.cpp
+++ b/framework/opengl/simplereference/sglrReferenceContext.cpp
@@ -3341,14 +3341,16 @@ void ReferenceContext::clear (deUint32 buffers)
        rr::MultisamplePixelBufferAccess        colorBuf0       = getDrawColorbuffer();
        rr::MultisamplePixelBufferAccess        depthBuf        = getDrawDepthbuffer();
        rr::MultisamplePixelBufferAccess        stencilBuf      = getDrawStencilbuffer();
-       bool                                                            hasColor0       = !isEmpty(colorBuf0);
-       bool                                                            hasDepth        = !isEmpty(depthBuf);
-       bool                                                            hasStencil      = !isEmpty(stencilBuf);
        IVec4                                                           baseArea        = m_scissorEnabled ? m_scissorBox : IVec4(0, 0, 0x7fffffff, 0x7fffffff);
+       IVec4                                                           colorArea       = intersect(baseArea, getBufferRect(colorBuf0));
+       IVec4                                                           depthArea       = intersect(baseArea, getBufferRect(depthBuf));
+       IVec4                                                           stencilArea     = intersect(baseArea, getBufferRect(stencilBuf));
+       bool                                                            hasColor0       = !isEmpty(colorArea);
+       bool                                                            hasDepth        = !isEmpty(depthArea);
+       bool                                                            hasStencil      = !isEmpty(stencilArea);
 
        if (hasColor0 && (buffers & GL_COLOR_BUFFER_BIT) != 0)
        {
-               IVec4                                                           colorArea       = intersect(baseArea, getBufferRect(colorBuf0));
                rr::MultisamplePixelBufferAccess        access          = rr::getSubregion(colorBuf0, colorArea.x(), colorArea.y(), colorArea.z(), colorArea.w());
                bool                                                            isSRGB          = tcu::isSRGB(colorBuf0.raw().getFormat());
                Vec4                                                            c                       = (isSRGB && m_sRGBUpdateEnabled) ? tcu::linearToSRGB(m_clearColor) : m_clearColor;
@@ -3369,7 +3371,6 @@ void ReferenceContext::clear (deUint32 buffers)
 
        if (hasDepth && (buffers & GL_DEPTH_BUFFER_BIT) != 0 && m_depthMask)
        {
-               IVec4                                                           depthArea                               = intersect(baseArea, getBufferRect(depthBuf));
                rr::MultisamplePixelBufferAccess        access                                  = rr::getSubregion(depthBuf, depthArea.x(), depthArea.y(), depthArea.z(), depthArea.w());
                bool                                                            isSharedDepthStencil    = depthBuf.raw().getFormat().order != tcu::TextureFormat::D;
 
@@ -3399,7 +3400,6 @@ void ReferenceContext::clear (deUint32 buffers)
 
        if (hasStencil && (buffers & GL_STENCIL_BUFFER_BIT) != 0)
        {
-               IVec4                                                           stencilArea                             = intersect(baseArea, getBufferRect(stencilBuf));
                rr::MultisamplePixelBufferAccess        access                                  = rr::getSubregion(stencilBuf, stencilArea.x(), stencilArea.y(), stencilArea.z(), stencilArea.w());
                int                                                                     stencilBits                             = getNumStencilBits(stencilBuf.raw().getFormat());
                int                                                                     stencil                                 = maskStencil(stencilBits, m_clearStencil);
@@ -3442,10 +3442,10 @@ void ReferenceContext::clearBufferiv (deUint32 buffer, int drawbuffer, const int
                rr::MultisamplePixelBufferAccess        colorBuf        = getDrawColorbuffer();
                bool                                                            maskUsed        = !m_colorMask[0] || !m_colorMask[1] || !m_colorMask[2] || !m_colorMask[3];
                bool                                                            maskZero        = !m_colorMask[0] && !m_colorMask[1] && !m_colorMask[2] && !m_colorMask[3];
+               IVec4                                                           area            = intersect(baseArea, getBufferRect(colorBuf));
 
-               if (!isEmpty(colorBuf) && !maskZero)
+               if (!isEmpty(area) && !maskZero)
                {
-                       IVec4                                                           area            = intersect(baseArea, getBufferRect(colorBuf));
                        rr::MultisamplePixelBufferAccess        access          = rr::getSubregion(colorBuf, area.x(), area.y(), area.z(), area.w());
                        IVec4                                                           color           (value[0], value[1], value[2], value[3]);
 
@@ -3464,11 +3464,11 @@ void ReferenceContext::clearBufferiv (deUint32 buffer, int drawbuffer, const int
        {
                TCU_CHECK_INTERNAL(buffer == GL_STENCIL);
 
-               rr::MultisamplePixelBufferAccess stencilBuf = getDrawStencilbuffer();
+               rr::MultisamplePixelBufferAccess        stencilBuf      = getDrawStencilbuffer();
+               IVec4                                                           area            = intersect(baseArea, getBufferRect(stencilBuf));
 
-               if (!isEmpty(stencilBuf) && m_stencil[rr::FACETYPE_FRONT].writeMask != 0)
+               if (!isEmpty(area) && m_stencil[rr::FACETYPE_FRONT].writeMask != 0)
                {
-                       IVec4                                                           area            = intersect(baseArea, getBufferRect(stencilBuf));
                        rr::MultisamplePixelBufferAccess        access          = rr::getSubregion(stencilBuf, area.x(), area.y(), area.z(), area.w());
                        int                                                                     stencil         = value[0];
 
@@ -3492,10 +3492,10 @@ void ReferenceContext::clearBufferfv (deUint32 buffer, int drawbuffer, const flo
                rr::MultisamplePixelBufferAccess        colorBuf        = getDrawColorbuffer();
                bool                                                            maskUsed        = !m_colorMask[0] || !m_colorMask[1] || !m_colorMask[2] || !m_colorMask[3];
                bool                                                            maskZero        = !m_colorMask[0] && !m_colorMask[1] && !m_colorMask[2] && !m_colorMask[3];
+               IVec4                                                           area            = intersect(baseArea, getBufferRect(colorBuf));
 
-               if (!isEmpty(colorBuf) && !maskZero)
+               if (!isEmpty(area) && !maskZero)
                {
-                       IVec4                                                           area            = intersect(baseArea, getBufferRect(colorBuf));
                        rr::MultisamplePixelBufferAccess        access          = rr::getSubregion(colorBuf, area.x(), area.y(), area.z(), area.w());
                        Vec4                                                            color           (value[0], value[1], value[2], value[3]);
 
@@ -3517,11 +3517,11 @@ void ReferenceContext::clearBufferfv (deUint32 buffer, int drawbuffer, const flo
        {
                TCU_CHECK_INTERNAL(buffer == GL_DEPTH);
 
-               rr::MultisamplePixelBufferAccess depthBuf = getDrawDepthbuffer();
+               rr::MultisamplePixelBufferAccess        depthBuf        = getDrawDepthbuffer();
+               IVec4                                                           area            = intersect(baseArea, getBufferRect(depthBuf));
 
-               if (!isEmpty(depthBuf) && m_depthMask)
+               if (!isEmpty(area) && m_depthMask)
                {
-                       IVec4                                                           area            = intersect(baseArea, getBufferRect(depthBuf));
                        rr::MultisamplePixelBufferAccess        access          = rr::getSubregion(depthBuf, area.x(), area.y(), area.z(), area.w());
                        float                                                           depth           = value[0];
 
@@ -3545,10 +3545,10 @@ void ReferenceContext::clearBufferuiv (deUint32 buffer, int drawbuffer, const de
                rr::MultisamplePixelBufferAccess        colorBuf        = getDrawColorbuffer();
                bool                                                            maskUsed        = !m_colorMask[0] || !m_colorMask[1] || !m_colorMask[2] || !m_colorMask[3];
                bool                                                            maskZero        = !m_colorMask[0] && !m_colorMask[1] && !m_colorMask[2] && !m_colorMask[3];
+               IVec4                                                           area            = intersect(baseArea, getBufferRect(colorBuf));
 
-               if (!isEmpty(colorBuf) && !maskZero)
+               if (!isEmpty(area) && !maskZero)
                {
-                       IVec4                                                           area            = intersect(baseArea, getBufferRect(colorBuf));
                        rr::MultisamplePixelBufferAccess        access          = rr::getSubregion(colorBuf, area.x(), area.y(), area.z(), area.w());
                        tcu::UVec4                                                      color           (value[0], value[1], value[2], value[3]);