Output the number of columns and rows written for robust ReadPixels.

extensions/ANGLE_robust_client_memory.txt

@@ -20,7 +20,7 @@ Status
 
 Version
 
-    Version 3, October 7, 2016
+    Version 4, March 30, 2017
 
 Number
 
@@ -65,7 +65,7 @@ New Procedures and Functions
     void GetVertexAttribfvRobustANGLE(uint index, enum pname, sizei bufSize, sizei *length, float *params)
     void GetVertexAttribivRobustANGLE(uint index, enum pname, sizei bufSize, sizei *length, int *params)
     void GetVertexAttribPointervRobustANGLE(uint index, enum pname, sizei bufSize, sizei *length, void **pointer)
-    void ReadPixelsRobustANGLE(int x, int y, sizei width, sizei height, enum format, enum type, sizei bufSize, sizei *length, void *pixels)
+    void ReadPixelsRobustANGLE(int x, int y, sizei width, sizei height, enum format, enum type, sizei bufSize, sizei *length, sizei *columns, sizei *rows, void *pixels)
     void TexImage2DRobustANGLE(enum target, int level, int internalformat, sizei width, sizei height, int border, enum format, enum type, sizei bufSize, const void *pixels)
     void TexParameterfvRobustANGLE(enum target, enum pname, sizei bufSize, const GLfloat *params)
     void TexParameterivRobustANGLE(enum target, enum pname, sizei bufSize, const GLint *params)
@@ -98,7 +98,7 @@ New Procedures and Functions
     void GetTexLevelParameterfvRobustANGLE(enum target, int level, enum pname, sizei bufSize, sizei *length, float *params)
 
     void GetPointervRobustANGLERobustANGLE(enum pname, sizei bufSize, sizei *length, void **params)
-    void ReadnPixelsRobustANGLE(int x, int y, sizei width, sizei height, enum format, enum type, sizei bufSize, sizei *length, void *data)
+    void ReadnPixelsRobustANGLE(int x, int y, sizei width, sizei height, enum format, enum type, sizei bufSize, sizei *length, sizei *columns, sizei *rows, void *data)
     void GetnUniformfvRobustANGLE(uint program, int location, sizei bufSize, sizei *length, float *params)
     void GetnUniformivRobustANGLE(uint program, int location, sizei bufSize, sizei *length, int *params)
     void GetnUniformuivRobustANGLE(uint program, int location, sizei bufSize, sizei *length, uint *params)
@@ -128,6 +128,12 @@ Additions to the OpenGL ES Specification:
     recieve the number of values written to the buffer.  When an error is
     generated nothing will be written to <length>.
 
+    The <columns> and <rows> parameters of ReadPixelsRobustANGLE and
+    ReadnPixelsRobustANGLE specify addresses of variables to recieve the number
+    of columns and rows of pixels written to the buffer which may be less than
+    the <width> and <height> parameters if they would have read outside of the
+    framebuffer.
+
     Calls to "xRobustANGLE" will generate errors under the same conditions as
     "x". Any instances of undefined behaviour in "x" will also be undefined in
     "xRobustANGLE".  For example, it is invalid to call
@@ -167,3 +173,4 @@ Revision History
       2   Sept 28, 2016  geofflang  Changed name from ANGLE_robust_queries to
                                     ANGLE_robust_client_memory, added issue 3.
       3   Oct 7, 2016    geofflang  Added and resolved issue 4.
+      4   Mar 30, 2017   geofflang  Added columns and rows to ReadPixels.

include/GLES2/gl2ext.h

@@ -3622,7 +3622,7 @@ typedef void (GL_APIENTRYP PFNGLGETUNIFORMIVROBUSTANGLE) (GLuint program, GLint
 typedef void (GL_APIENTRYP PFNGLGETVERTEXATTRIBFVROBUSTANGLE) (GLuint index, GLenum pname, GLsizei bufSize, GLsizei *length, GLfloat *params);
 typedef void (GL_APIENTRYP PFNGLGETVERTEXATTRIBIVROBUSTANGLE) (GLuint index, GLenum pname, GLsizei bufSize, GLsizei *length, GLint *params);
 typedef void (GL_APIENTRYP PFNGLGETVERTEXATTRIBPOINTERVROBUSTANGLE) (GLuint index, GLenum pname, GLsizei bufSize, GLsizei *length, void **pointer);
-typedef void (GL_APIENTRYP PFNGLREADPIXELSROBUSTANGLE) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, void *pixels);
+typedef void (GL_APIENTRYP PFNGLREADPIXELSROBUSTANGLE) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, GLsizei *columns, GLsizei *rows, void *pixels);
 typedef void (GL_APIENTRYP PFNGLTEXIMAGE2DROBUSTANGLE) (GLenum target, GLint level, GLint internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, GLsizei bufSize, const void *pixels);
 typedef void (GL_APIENTRYP PFNGLTEXPARAMETERFVROBUSTANGLE) (GLenum target, GLenum pname, GLsizei bufSize, const GLfloat *params);
 typedef void (GL_APIENTRYP PFNGLTEXPARAMETERIVROBUSTANGLE) (GLenum target, GLenum pname, GLsizei bufSize, const GLint *params);
@@ -3652,7 +3652,7 @@ typedef void (GL_APIENTRYP PFNGLGETMULTISAMPLEFVROBUSTANGLE) (GLenum pname, GLui
 typedef void (GL_APIENTRYP PFNGLGETTEXLEVELPARAMETERIVROBUSTANGLE) (GLenum target, GLint level, GLenum pname, GLsizei bufSize, GLsizei *length, GLint *params);
 typedef void (GL_APIENTRYP PFNGLGETTEXLEVELPARAMETERFVROBUSTANGLE) (GLenum target, GLint level, GLenum pname, GLsizei bufSize, GLsizei *length, GLfloat *params);
 typedef void (GL_APIENTRYP PFNGLGETPOINTERVROBUSTANGLEROBUSTANGLE) (GLenum pname, GLsizei bufSize, GLsizei *length, void **params);
-typedef void (GL_APIENTRYP PFNGLREADNPIXELSROBUSTANGLE) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, void *data);
+typedef void (GL_APIENTRYP PFNGLREADNPIXELSROBUSTANGLE) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, GLsizei *columns, GLsizei *rows, void *data);
 typedef void (GL_APIENTRYP PFNGLGETNUNIFORMFVROBUSTANGLE) (GLuint program, GLint location, GLsizei bufSize, GLsizei *length, GLfloat *params);
 typedef void (GL_APIENTRYP PFNGLGETNUNIFORMIVROBUSTANGLE) (GLuint program, GLint location, GLsizei bufSize, GLsizei *length, GLint *params);
 typedef void (GL_APIENTRYP PFNGLGETNUNIFORMUIVROBUSTANGLE) (GLuint program, GLint location, GLsizei bufSize, GLsizei *length, GLuint *params);
@@ -3683,7 +3683,7 @@ GL_APICALL void GL_APIENTRY glGetUniformivRobustANGLE (GLuint program, GLint loc
 GL_APICALL void GL_APIENTRY glGetVertexAttribfvRobustANGLE (GLuint index, GLenum pname, GLsizei bufSize, GLsizei *length, GLfloat *params);
 GL_APICALL void GL_APIENTRY glGetVertexAttribivRobustANGLE (GLuint index, GLenum pname, GLsizei bufSize, GLsizei *length, GLint *params);
 GL_APICALL void GL_APIENTRY glGetVertexAttribPointervRobustANGLE (GLuint index, GLenum pname, GLsizei bufSize, GLsizei *length, void **pointer);
-GL_APICALL void GL_APIENTRY glReadPixelsRobustANGLE (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, void *pixels);
+GL_APICALL void GL_APIENTRY glReadPixelsRobustANGLE (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, GLsizei *columns, GLsizei *rows, void *pixels);
 GL_APICALL void GL_APIENTRY glTexImage2DRobustANGLE (GLenum target, GLint level, GLint internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, GLsizei bufSize, const void *pixels);
 GL_APICALL void GL_APIENTRY glTexParameterfvRobustANGLE (GLenum target, GLenum pname, GLsizei bufSize, const GLfloat *params);
 GL_APICALL void GL_APIENTRY glTexParameterivRobustANGLE (GLenum target, GLenum pname, GLsizei bufSize, const GLint *params);
@@ -3713,7 +3713,7 @@ GL_APICALL void GL_APIENTRY glGetMultisamplefvRobustANGLE (GLenum pname, GLuint
 GL_APICALL void GL_APIENTRY glGetTexLevelParameterivRobustANGLE (GLenum target, GLint level, GLenum pname, GLsizei bufSize, GLsizei *length, GLint *params);
 GL_APICALL void GL_APIENTRY glGetTexLevelParameterfvRobustANGLE (GLenum target, GLint level, GLenum pname, GLsizei bufSize, GLsizei *length, GLfloat *params);
 GL_APICALL void GL_APIENTRY glGetPointervRobustANGLERobustANGLE (GLenum pname, GLsizei bufSize, GLsizei *length, void **params);
-GL_APICALL void GL_APIENTRY glReadnPixelsRobustANGLE (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, void *data);
+GL_APICALL void GL_APIENTRY glReadnPixelsRobustANGLE (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei bufSize, GLsizei *length, GLsizei *columns, GLsizei *rows, void *data);
 GL_APICALL void GL_APIENTRY glGetnUniformfvRobustANGLE (GLuint program, GLint location, GLsizei bufSize, GLsizei *length, GLfloat *params);
 GL_APICALL void GL_APIENTRY glGetnUniformivRobustANGLE (GLuint program, GLint location, GLsizei bufSize, GLsizei *length, GLint *params);
 GL_APICALL void GL_APIENTRY glGetnUniformuivRobustANGLE (GLuint program, GLint location, GLsizei bufSize, GLsizei *length, GLuint *params);

src/libANGLE/validationES.cpp

@@ -233,12 +233,22 @@ bool ValidateReadPixelsBase(ValidationContext *context,
                             GLenum type,
                             GLsizei bufSize,
                             GLsizei *length,
+                            GLsizei *columns,
+                            GLsizei *rows,
                             GLvoid *pixels)
 {
     if (length != nullptr)
     {
         *length = 0;
     }
+    if (rows != nullptr)
+    {
+        *rows = 0;
+    }
+    if (columns != nullptr)
+    {
+        *columns = 0;
+    }
 
     if (width < 0 || height < 0)
     {
@@ -320,8 +330,7 @@ bool ValidateReadPixelsBase(ValidationContext *context,
     size_t endByte = endByteOrErr.getResult();
     if (bufSize >= 0)
     {
-
-        if (static_cast<size_t>(bufSize) < endByte)
+        if (pixelPackBuffer == nullptr && static_cast<size_t>(bufSize) < endByte)
         {
             context->handleError(
                 Error(GL_INVALID_OPERATION, "bufSize must be at least %u bytes.", endByte));
@@ -344,7 +353,7 @@ bool ValidateReadPixelsBase(ValidationContext *context,
         }
     }
 
-    if (length != nullptr)
+    if (pixelPackBuffer == nullptr && length != nullptr)
     {
         if (endByte > static_cast<size_t>(std::numeric_limits<GLsizei>::max()))
         {
@@ -356,6 +365,39 @@ bool ValidateReadPixelsBase(ValidationContext *context,
         *length = static_cast<GLsizei>(endByte);
     }
 
+    auto getClippedExtent = [](GLint start, GLsizei length, int bufferSize) {
+        angle::CheckedNumeric<int> clippedExtent(length);
+        if (start < 0)
+        {
+            // "subtract" the area that is less than 0
+            clippedExtent += start;
+        }
+
+        const int readExtent = start + length;
+        if (readExtent > bufferSize)
+        {
+            // Subtract the region to the right of the read buffer
+            clippedExtent -= (readExtent - bufferSize);
+        }
+
+        if (!clippedExtent.IsValid())
+        {
+            return 0;
+        }
+
+        return std::max(clippedExtent.ValueOrDie(), 0);
+    };
+
+    if (columns != nullptr)
+    {
+        *columns = getClippedExtent(x, width, readBuffer->getSize().width);
+    }
+
+    if (rows != nullptr)
+    {
+        *rows = getClippedExtent(y, height, readBuffer->getSize().height);
+    }
+
     return true;
 }
 
@@ -2326,7 +2368,8 @@ bool ValidateReadPixels(ValidationContext *context,
                         GLenum type,
                         GLvoid *pixels)
 {
-    return ValidateReadPixelsBase(context, x, y, width, height, format, type, -1, nullptr, pixels);
+    return ValidateReadPixelsBase(context, x, y, width, height, format, type, -1, nullptr, nullptr,
+                                  nullptr, pixels);
 }
 
 bool ValidateReadPixelsRobustANGLE(ValidationContext *context,
@@ -2338,6 +2381,8 @@ bool ValidateReadPixelsRobustANGLE(ValidationContext *context,
                                    GLenum type,
                                    GLsizei bufSize,
                                    GLsizei *length,
+                                   GLsizei *columns,
+                                   GLsizei *rows,
                                    GLvoid *pixels)
 {
     if (!ValidateRobustEntryPoint(context, bufSize))
@@ -2346,7 +2391,7 @@ bool ValidateReadPixelsRobustANGLE(ValidationContext *context,
     }
 
     if (!ValidateReadPixelsBase(context, x, y, width, height, format, type, bufSize, length,
-                                pixels))
+                                columns, rows, pixels))
     {
         return false;
     }
@@ -2376,7 +2421,7 @@ bool ValidateReadnPixelsEXT(Context *context,
     }
 
     return ValidateReadPixelsBase(context, x, y, width, height, format, type, bufSize, nullptr,
-                                  pixels);
+                                  nullptr, nullptr, pixels);
 }
 
 bool ValidateReadnPixelsRobustANGLE(ValidationContext *context,
@@ -2388,6 +2433,8 @@ bool ValidateReadnPixelsRobustANGLE(ValidationContext *context,
                                     GLenum type,
                                     GLsizei bufSize,
                                     GLsizei *length,
+                                    GLsizei *columns,
+                                    GLsizei *rows,
                                     GLvoid *data)
 {
     if (!ValidateRobustEntryPoint(context, bufSize))
@@ -2395,7 +2442,8 @@ bool ValidateReadnPixelsRobustANGLE(ValidationContext *context,
         return false;
     }
 
-    if (!ValidateReadPixelsBase(context, x, y, width, height, format, type, bufSize, length, data))
+    if (!ValidateReadPixelsBase(context, x, y, width, height, format, type, bufSize, length,
+                                columns, rows, data))
     {
         return false;
     }

src/libANGLE/validationES.h

@@ -124,6 +124,8 @@ bool ValidateReadPixelsRobustANGLE(ValidationContext *context,
                                    GLenum type,
                                    GLsizei bufSize,
                                    GLsizei *length,
+                                   GLsizei *columns,
+                                   GLsizei *rows,
                                    GLvoid *pixels);
 bool ValidateReadnPixelsEXT(Context *context,
                             GLint x,
@@ -143,6 +145,8 @@ bool ValidateReadnPixelsRobustANGLE(ValidationContext *context,
                                     GLenum type,
                                     GLsizei bufSize,
                                     GLsizei *length,
+                                    GLsizei *columns,
+                                    GLsizei *rows,
                                     GLvoid *data);
 
 bool ValidateGenQueriesEXT(gl::Context *context, GLsizei n);

src/libGLESv2/entry_points_gles_2_0_ext.cpp

@@ -2387,20 +2387,24 @@ ANGLE_EXPORT void GL_APIENTRY ReadPixelsRobustANGLE(GLint x,
                                                     GLenum type,
                                                     GLsizei bufSize,
                                                     GLsizei *length,
+                                                    GLsizei *columns,
+                                                    GLsizei *rows,
                                                     void *pixels)
 {
     EVENT(
         "(GLint x = %d, GLint y = %d, GLsizei width = %d, GLsizei height = %d, "
         "GLenum format = 0x%X, GLenum type = 0x%X, GLsizei bufsize = %d, GLsizei* length = "
-        "0x%0.8p, GLvoid* pixels = 0x%0.8p)",
-        x, y, width, height, format, type, bufSize, length, pixels);
+        "0x%0.8p, GLsizei* columns = 0x%0.8p, GLsizei* rows = 0x%0.8p, GLvoid* pixels = 0x%0.8p)",
+        x, y, width, height, format, type, bufSize, length, columns, rows, pixels);
 
     Context *context = GetValidGlobalContext();
     if (context)
     {
         GLsizei writeLength = 0;
+        GLsizei writeColumns = 0;
+        GLsizei writeRows    = 0;
         if (!ValidateReadPixelsRobustANGLE(context, x, y, width, height, format, type, bufSize,
-                                           &writeLength, pixels))
+                                           &writeLength, &writeColumns, &writeRows, pixels))
         {
             return;
         }
@@ -2408,6 +2412,8 @@ ANGLE_EXPORT void GL_APIENTRY ReadPixelsRobustANGLE(GLint x,
         context->readPixels(x, y, width, height, format, type, pixels);
 
         SetRobustLengthParam(length, writeLength);
+        SetRobustLengthParam(columns, writeColumns);
+        SetRobustLengthParam(rows, writeRows);
     }
 }
 
@@ -3108,20 +3114,24 @@ ANGLE_EXPORT void GL_APIENTRY ReadnPixelsRobustANGLE(GLint x,
                                                      GLenum type,
                                                      GLsizei bufSize,
                                                      GLsizei *length,
+                                                     GLsizei *columns,
+                                                     GLsizei *rows,
                                                      void *data)
 {
     EVENT(
         "(GLint x = %d, GLint y = %d, GLsizei width = %d, GLsizei height = %d, "
         "GLenum format = 0x%X, GLenum type = 0x%X, GLsizei bufsize = %d, GLsizei* length = "
-        "0x%0.8p, GLvoid *data = 0x%0.8p)",
-        x, y, width, height, format, type, bufSize, length, data);
+        "0x%0.8p, GLsizei* columns = 0x%0.8p, GLsizei* rows = 0x%0.8p, GLvoid *data = 0x%0.8p)",
+        x, y, width, height, format, type, bufSize, length, columns, rows, data);
 
     Context *context = GetValidGlobalContext();
     if (context)
     {
         GLsizei writeLength = 0;
+        GLsizei writeColumns = 0;
+        GLsizei writeRows    = 0;
         if (!ValidateReadnPixelsRobustANGLE(context, x, y, width, height, format, type, bufSize,
-                                            &writeLength, data))
+                                            &writeLength, &writeColumns, &writeRows, data))
         {
             return;
         }
@@ -3129,6 +3139,8 @@ ANGLE_EXPORT void GL_APIENTRY ReadnPixelsRobustANGLE(GLint x,
         context->readPixels(x, y, width, height, format, type, data);
 
         SetRobustLengthParam(length, writeLength);
+        SetRobustLengthParam(columns, writeColumns);
+        SetRobustLengthParam(rows, writeRows);
     }
 }
 

src/libGLESv2/entry_points_gles_2_0_ext.h

@@ -353,6 +353,8 @@ ANGLE_EXPORT void GL_APIENTRY ReadPixelsRobustANGLE(GLint x,
                                                     GLenum type,
                                                     GLsizei bufSize,
                                                     GLsizei *length,
+                                                    GLsizei *columns,
+                                                    GLsizei *rows,
                                                     void *pixels);
 ANGLE_EXPORT void GL_APIENTRY TexImage2DRobustANGLE(GLenum target,
                                                     GLint level,
@@ -529,6 +531,8 @@ ANGLE_EXPORT void GL_APIENTRY ReadnPixelsRobustANGLE(GLint x,
                                                      GLenum type,
                                                      GLsizei bufSize,
                                                      GLsizei *length,
+                                                     GLsizei *columns,
+                                                     GLsizei *rows,
                                                      void *data);
 ANGLE_EXPORT void GL_APIENTRY GetnUniformfvRobustANGLE(GLuint program,
                                                        GLint location,

src/tests/gl_tests/RobustClientMemoryTest.cpp

@@ -12,13 +12,16 @@
 
 namespace angle
 {
+
+constexpr GLsizei kWindowSize = 128;
+
 class RobustClientMemoryTest : public ANGLETest
 {
   protected:
     RobustClientMemoryTest()
     {
-        setWindowWidth(128);
-        setWindowHeight(128);
+        setWindowWidth(kWindowSize);
+        setWindowHeight(kWindowSize);
         setConfigRedBits(8);
         setConfigGreenBits(8);
         setConfigBlueBits(8);
@@ -357,14 +360,29 @@ TEST_P(RobustClientMemoryTest, ReadPixels)
 
     // Test the regular case
     GLsizei length = 0;
+    GLsizei width  = 0;
+    GLsizei height = 0;
     glReadPixelsRobustANGLE(0, 0, dataDimension, dataDimension, GL_RGBA, GL_UNSIGNED_BYTE,
-                            static_cast<GLsizei>(rgbaData.size()), &length, rgbaData.data());
+                            static_cast<GLsizei>(rgbaData.size()), &length, &width, &height,
+                            rgbaData.data());
+    EXPECT_GL_NO_ERROR();
+    EXPECT_EQ(static_cast<GLsizei>(rgbaData.size()), length);
+    EXPECT_EQ(dataDimension, width);
+    EXPECT_EQ(dataDimension, height);
+
+    // Test a case that would be partially clipped
+    glReadPixelsRobustANGLE(-1, kWindowSize - dataDimension + 3, dataDimension, dataDimension,
+                            GL_RGBA, GL_UNSIGNED_BYTE, static_cast<GLsizei>(rgbaData.size()),
+                            &length, &width, &height, rgbaData.data());
     EXPECT_GL_NO_ERROR();
     EXPECT_EQ(static_cast<GLsizei>(rgbaData.size()), length);
+    EXPECT_EQ(dataDimension - 1, width);
+    EXPECT_EQ(dataDimension - 3, height);
 
     // Test with a data size that is too small
     glReadPixelsRobustANGLE(0, 0, dataDimension, dataDimension, GL_RGBA, GL_UNSIGNED_BYTE,
-                            static_cast<GLsizei>(rgbaData.size()) - 1, &length, rgbaData.data());
+                            static_cast<GLsizei>(rgbaData.size()) - 1, &length, nullptr, nullptr,
+                            rgbaData.data());
     EXPECT_GL_ERROR(GL_INVALID_OPERATION);
 
     if (getClientMajorVersion() >= 3)
@@ -372,7 +390,8 @@ TEST_P(RobustClientMemoryTest, ReadPixels)
         // Set a pack parameter that would cause the driver to write past the end of the buffer
         glPixelStorei(GL_PACK_ROW_LENGTH, dataDimension + 1);
         glReadPixelsRobustANGLE(0, 0, dataDimension, dataDimension, GL_RGBA, GL_UNSIGNED_BYTE,
-                                static_cast<GLsizei>(rgbaData.size()), &length, rgbaData.data());
+                                static_cast<GLsizei>(rgbaData.size()), &length, nullptr, nullptr,
+                                rgbaData.data());
         EXPECT_GL_ERROR(GL_INVALID_OPERATION);
     }
 }