1 files changed, 188 insertions, 0 deletions
diff --git a/vcl/inc/opengl/RenderState.hxx b/vcl/inc/opengl/RenderState.hxx
new file mode 100644
index 000000000..3a89344e2
--- /dev/null
+++ b/vcl/inc/opengl/RenderState.hxx
@@ -0,0 +1,188 @@
+/* -*- 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/.
+ *
+ */
+
+#ifndef INCLUDED_VCL_INC_OPENGL_RENDER_STATE_H
+#define INCLUDED_VCL_INC_OPENGL_RENDER_STATE_H
+
+#include <opengl/TextureState.hxx>
+
+template<GLenum ENUM_TYPE, typename TYPE>
+class GenericCapabilityState
+{
+protected:
+    bool mbTest;
+
+    GenericCapabilityState()
+        : mbTest(false)
+    {
+    }
+
+    static bool readState()
+    {
+        return glIsEnabled(ENUM_TYPE);
+    }
+
+public:
+    void sync()
+    {
+        mbTest = readState();
+    }
+
+    void enable()
+    {
+        if (!mbTest)
+        {
+            glEnable(ENUM_TYPE);
+            CHECK_GL_ERROR();
+            mbTest = true;
+        }
+        else
+        {
+            VCL_GL_INFO(TYPE::className() << ": enable called but already enabled");
+        }
+#ifdef DBG_UTIL
+        checkState();
+#endif
+    }
+
+    void disable()
+    {
+        if (mbTest)
+        {
+            glDisable(ENUM_TYPE);
+            CHECK_GL_ERROR();
+            mbTest = false;
+        }
+        else
+        {
+            VCL_GL_INFO(TYPE::className() << ": disable called but already disabled");
+        }
+#ifdef DBG_UTIL
+        checkState();
+#endif
+    }
+
+#ifdef DBG_UTIL
+    void checkState()
+    {
+        bool bRealState = readState();
+        if (mbTest != bRealState)
+        {
+            VCL_GL_INFO(TYPE::className() << " mismatch! "
+                            << "Expected: " << (mbTest ? "enabled" : "disabled")
+                            << " but is: "        << (bRealState ? "enabled" : "disabled"));
+        }
+    }
+#endif
+};
+
+class ScissorState : public GenericCapabilityState<GL_SCISSOR_TEST, ScissorState>
+{
+private:
+    int mX;
+    int mY;
+    int mWidth;
+    int mHeight;
+
+public:
+    static std::string className() { return std::string("ScissorState"); }
+
+    ScissorState()
+        : mX(0)
+        , mY(0)
+        , mWidth(0)
+        , mHeight(0)
+    {}
+
+    void set(int x, int y, int width, int height)
+    {
+        if (x != mX || y != mY || width != mWidth || height != mHeight)
+        {
+            glScissor(x, y, width, height);
+            CHECK_GL_ERROR();
+
+            mX = x;
+            mY = y;
+            mWidth = width;
+            mHeight = height;
+        }
+    }
+};
+
+class StencilState : public GenericCapabilityState<GL_STENCIL_TEST, StencilState>
+{
+public:
+    static std::string className() { return std::string("StencilState"); }
+};
+
+class BlendState : public GenericCapabilityState<GL_BLEND, BlendState>
+{
+    GLenum mnSourceMode;
+    GLenum mnDestinationMode;
+public:
+    BlendState()
+        : mnSourceMode(GL_ZERO)
+        , mnDestinationMode(GL_ZERO)
+    {}
+
+    static std::string className() { return std::string("BlendState"); }
+
+    void func(GLenum nSource, GLenum nDestination)
+    {
+        if (mnSourceMode != nSource || mnDestinationMode != nDestination)
+        {
+            glBlendFunc(nSource, nDestination);
+            CHECK_GL_ERROR();
+            mnSourceMode = nSource;
+            mnDestinationMode = nDestination;
+        }
+    }
+};
+
+class RenderState
+{
+    TextureState maTexture;
+    ScissorState maScissor;
+    StencilState maStencil;
+    BlendState   maBlend;
+
+    tools::Rectangle maCurrentViewport;
+
+public:
+    RenderState()
+    {}
+
+    void viewport(tools::Rectangle aViewPort)
+    {
+        if (aViewPort != maCurrentViewport)
+        {
+            glViewport(aViewPort.Left(), aViewPort.Top(), aViewPort.GetWidth(), aViewPort.GetHeight());
+            CHECK_GL_ERROR();
+            maCurrentViewport = aViewPort;
+        }
+    }
+
+    TextureState& texture() { return maTexture; }
+    ScissorState& scissor() { return maScissor; }
+    StencilState& stencil() { return maStencil; }
+    BlendState&   blend()   { return maBlend; }
+
+    void sync()
+    {
+        VCL_GL_INFO("RenderState::sync");
+        maScissor.sync();
+        maStencil.sync();
+        maBlend.sync();
+    }
+};
+
+#endif // INCLUDED_VCL_INC_OPENGL_RENDER_STATE_H
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */