vcl: Only load OpenGL shaders once for each context

Change-Id: Idbf9026c5e64ef41d4c913153dfddf36923ff7de

1 files changed, 238 insertions, 0 deletions

diff --git a/vcl/opengl/program.cxx b/vcl/opengl/program.cxx
new file mode 100644
index 000000000000..c9542c726c75
--- /dev/null
+++ b/vcl/opengl/program.cxx
@@ -0,0 +1,238 @@
+/* -*- 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/.
+ */
+
+#include <opengl/program.hxx>
+
+#include <vcl/opengl/OpenGLHelper.hxx>
+
+#include <glm/glm.hpp>
+#include <glm/gtc/type_ptr.hpp>
+
+OpenGLProgram::OpenGLProgram() :
+    mnId( 0 ),
+    mnEnabledAttribs( 0 ),
+    mnAttribIndex( 0 ),
+    mnPositionAttrib( SAL_MAX_UINT32 ),
+    mnTexCoordAttrib( SAL_MAX_UINT32 ),
+    mnAlphaCoordAttrib( SAL_MAX_UINT32 ),
+    mbBlending( false )
+{
+}
+
+OpenGLProgram::~OpenGLProgram()
+{
+    maUniformLocations.clear();
+    if( mnId != 0 )
+        glDeleteProgram( mnId );
+}
+
+bool OpenGLProgram::Load( const OUString& rVertexShader, const OUString& rFragmentShader )
+{
+    mnId = OpenGLHelper::LoadShaders( rVertexShader, rFragmentShader );
+    return ( mnId != 0 );
+}
+
+bool OpenGLProgram::Use()
+{
+    if( !mnId )
+        return false;
+
+    glUseProgram( mnId );
+    return true;
+}
+
+bool OpenGLProgram::Clean()
+{
+    // unbind all textures
+    if( !maTextures.empty() )
+    {
+        int nIndex( maTextures.size() - 1 );
+        TextureList::reverse_iterator it( maTextures.rbegin() );
+        while( it != maTextures.rend() )
+        {
+            glActiveTexture( GL_TEXTURE0 + nIndex-- );
+            it->Unbind();
+            it++;
+        }
+        maTextures.clear();
+    }
+
+    // disable any enabled vertex attrib array
+    if( mnEnabledAttribs )
+    {
+        for( int i = 0; i < 32; i++ )
+        {
+            if( mnEnabledAttribs & ( 1 << i ) )
+                glDisableVertexAttribArray( i );
+        }
+        mnEnabledAttribs = 0;
+    }
+
+    // disable blending if enabled
+    if( mbBlending )
+    {
+        mbBlending = false;
+        glDisable( GL_BLEND );
+    }
+
+    CHECK_GL_ERROR();
+    return true;
+}
+
+void OpenGLProgram::SetVertexAttrib( GLuint& rAttrib, const OString& rName, const GLvoid* pData )
+{
+    if( rAttrib == SAL_MAX_UINT32 )
+        rAttrib = glGetAttribLocation( mnId, (char*) rName.getStr() );
+    if( (mnEnabledAttribs & ( 1 << rAttrib )) == 0 )
+    {
+        glEnableVertexAttribArray( rAttrib );
+        mnEnabledAttribs |= ( 1 << rAttrib );
+    }
+    glVertexAttribPointer( rAttrib, 2, GL_FLOAT, GL_FALSE, 0, pData );
+}
+
+void OpenGLProgram::SetVertices( const GLvoid* pData )
+{
+    SetVertexAttrib( mnPositionAttrib, "position", pData );
+}
+
+void OpenGLProgram::SetTextureCoord( const GLvoid* pData )
+{
+    SetVertexAttrib( mnTexCoordAttrib, "tex_coord_in", pData );
+}
+
+void OpenGLProgram::SetAlphaCoord( const GLvoid* pData )
+{
+    SetVertexAttrib( mnAlphaCoordAttrib, "alpha_coord_in", pData );
+}
+
+GLuint OpenGLProgram::GetUniformLocation( const OString& rName )
+{
+    boost::unordered_map<OString, GLuint>::iterator it;
+
+    it = maUniformLocations.find( rName );
+    if( it == maUniformLocations.end() )
+    {
+        GLuint nLocation = glGetUniformLocation( mnId, (char*) rName.getStr() );
+        maUniformLocations[rName] = nLocation;
+        return nLocation;
+    }
+
+    return it->second;
+}
+
+void OpenGLProgram::SetUniform2f( const OString& rName, GLfloat v1, GLfloat v2 )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    glUniform2f( nUniform, v1, v2 );
+}
+
+void OpenGLProgram::SetUniform1fv( const OString& rName, GLsizei nCount, GLfloat* aValues )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    glUniform1fv( nUniform, nCount, aValues );
+}
+
+void OpenGLProgram::SetUniform2fv( const OString& rName, GLsizei nCount, GLfloat* aValues )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    glUniform2fv( nUniform, nCount, aValues );
+}
+
+void OpenGLProgram::SetColor( const OString& rName, SalColor nColor, sal_uInt8 nTransparency )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    glUniform4f( nUniform,
+                 ((float) SALCOLOR_RED( nColor )) / 255,
+                 ((float) SALCOLOR_GREEN( nColor )) / 255,
+                 ((float) SALCOLOR_BLUE( nColor )) / 255,
+                 (100 - nTransparency) * (1.0 / 100) );
+
+    if( nTransparency > 0 )
+        SetBlendMode( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
+}
+
+void OpenGLProgram::SetColorf( const OString& rName, SalColor nColor, double fTransparency )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    glUniform4f( nUniform,
+                 ((float) SALCOLOR_RED( nColor )) / 255,
+                 ((float) SALCOLOR_GREEN( nColor )) / 255,
+                 ((float) SALCOLOR_BLUE( nColor )) / 255,
+                 (1.0f - fTransparency) );
+
+    if( fTransparency > 0.0 )
+        SetBlendMode( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
+}
+
+void OpenGLProgram::SetColorWithIntensity( const OString& rName, const Color& rColor, long nFactor )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    glUniform4f( nUniform,
+                 ((float) rColor.GetRed()) * nFactor / 25500.0,
+                 ((float) rColor.GetGreen()) * nFactor / 25500.0,
+                 ((float) rColor.GetBlue()) * nFactor / 25500.0,
+                 1.0f );
+}
+
+void OpenGLProgram::SetTexture( const OString& rName, OpenGLTexture& rTexture )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    int nIndex = maTextures.size();
+
+    glUniform1i( nUniform, nIndex );
+    glActiveTexture( GL_TEXTURE0 + nIndex );
+    rTexture.Bind();
+    maTextures.push_back( rTexture );
+}
+
+void OpenGLProgram::SetTransform(
+    const OString& rName,
+    const OpenGLTexture& rTexture,
+    const basegfx::B2DPoint& rNull,
+    const basegfx::B2DPoint& rX,
+    const basegfx::B2DPoint& rY )
+{
+    GLuint nUniform = GetUniformLocation( rName );
+    const basegfx::B2DVector aXRel = rX - rNull;
+    const basegfx::B2DVector aYRel = rY - rNull;
+    const float aValues[] = {
+        (float) aXRel.getX()/rTexture.GetWidth(),  (float) aXRel.getY()/rTexture.GetWidth(),  0, 0,
+        (float) aYRel.getX()/rTexture.GetHeight(), (float) aYRel.getY()/rTexture.GetHeight(), 0, 0,
+        0,                                         0,                                         1, 0,
+        (float) rNull.getX(),                      (float) rNull.getY(),                      0, 1 };
+    glm::mat4 mMatrix = glm::make_mat4( aValues );
+    glUniformMatrix4fv( nUniform, 1, GL_FALSE, glm::value_ptr( mMatrix ) );
+}
+
+void OpenGLProgram::SetBlendMode( GLenum nSFactor, GLenum nDFactor )
+{
+    glEnable( GL_BLEND );
+    glBlendFunc( nSFactor, nDFactor );
+    mbBlending = true;
+}
+
+bool OpenGLProgram::DrawTexture( OpenGLTexture& rTexture )
+{
+    GLfloat aPosition[8] = { -1, -1, -1, 1, 1, 1, 1, -1 };
+    GLfloat aTexCoord[8];
+
+    if( !rTexture )
+        return false;
+
+    rTexture.GetWholeCoord( aTexCoord );
+    SetVertices( aPosition );
+    SetTextureCoord( aTexCoord );
+    glDrawArrays( GL_TRIANGLE_FAN, 0, 4 );
+    CHECK_GL_ERROR();
+
+    return true;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */