vcl: Add class to control a OpenGL texture

Change-Id: I76f3a27dfb4343db27804dacc98bd3dd57279d82

vcl/Library_vcl.mk

@@ -124,6 +124,7 @@ $(eval $(call gb_Library_use_externals,vcl,\
 $(eval $(call gb_Library_add_exception_objects,vcl,\
 	vcl/opengl/gdiimpl \
 	vcl/opengl/salbmp \
+	vcl/opengl/texture \
     vcl/source/opengl/OpenGLContext \
     vcl/source/opengl/OpenGLHelper \
     vcl/source/window/openglwin \

vcl/opengl/texture.cxx

+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "texture.hxx"
+
+OpenGLTexture::OpenGLTexture()
+: mnTexture( 0 )
+, mnWidth( -1 )
+, mnHeight( -1 )
+{
+}
+
+OpenGLTexture::OpenGLTexture( int nWidth, int nHeight )
+: mnTexture( 0 )
+, mnWidth( nWidth )
+, mnHeight( nHeight )
+{
+    glGenTextures( 1, &mnTexture );
+    glBindTexture( GL_TEXTURE_2D, mnTexture );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, nWidth, nHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL );
+    glBindTexture( GL_TEXTURE_2D, 0 );
+}
+
+OpenGLTexture::~OpenGLTexture()
+{
+    if( mnTexture != 0 )
+        glDeleteTextures( 1, &mnTexture );
+}
+
+GLuint OpenGLTexture::Id() const
+{
+    return mnTexture;
+}
+
+void OpenGLTexture::Bind()
+{
+    glBindTexture( GL_TEXTURE_2D, mnTexture );
+}
+
+void OpenGLTexture::Unbind()
+{
+    glBindTexture( GL_TEXTURE_2D, 0 );
+}
+
+bool OpenGLTexture::Draw()
+{
+    const GLfloat aPosition[8] = { -1, -1, -1, 1, 1, 1, 1, -1 };
+    const GLfloat aTexCoord[8] = {  0,  0,  0, 1, 1, 1, 1,  0 };
+
+    if( mnTexture == 0 )
+        return false;
+
+    glBindTexture( GL_TEXTURE_2D, mnTexture );
+    glEnableVertexAttribArray( 0 );
+    glVertexAttribPointer( 0, 2, GL_FLOAT, GL_FALSE, 0, aPosition );
+    glEnableVertexAttribArray( 1 );
+    glVertexAttribPointer( 1, 2, GL_FLOAT, GL_FALSE, 0, aTexCoord );
+    glDrawArrays( GL_TRIANGLE_FAN, 0, 4 );
+    glDisableVertexAttribArray( 0 );
+    glDisableVertexAttribArray( 1 );
+    glBindTexture( GL_TEXTURE_2D, 0 );
+
+    return true;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */

vcl/opengl/texture.hxx

+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#ifndef INCLUDED_VCL_OPENGL_TEXTURE_H
+#define INCLUDED_VCL_OPENGL_TEXTURE_H
+
+#include <boost/shared_ptr.hpp>
+#include <GL/glew.h>
+
+class OpenGLTexture
+{
+private:
+    GLuint mnTexture;
+    int    mnWidth;
+    int    mnHeight;
+
+public:
+    OpenGLTexture();
+    OpenGLTexture( int nWidth, int nHeight );
+    virtual ~OpenGLTexture();
+
+    GLuint Id() const;
+    void Bind();
+    void Unbind();
+    bool Draw();
+};
+
+typedef boost::shared_ptr< OpenGLTexture > OpenGLTextureSharedPtr;
+
+#endif // INCLUDED_VCL_OPENGL_TEXTURE_H
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */