initial empty Skia VCL implementation

This mostly duplicates OpenGL cases. Pretty much all implementation
methods are empty.

Change-Id: I333506f56dcc46c3e9405fe8194c172de17c54fd

1 files changed, 72 insertions, 0 deletions

diff --git a/vcl/skia/SkiaHelper.cxx b/vcl/skia/SkiaHelper.cxx
new file mode 100644
index 000000000000..1d2cf20d9c0b
--- /dev/null
+++ b/vcl/skia/SkiaHelper.cxx
@@ -0,0 +1,72 @@
+/* -*- 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 <vcl/skia/SkiaHelper.hxx>
+
+#include <vcl/svapp.hxx>
+
+bool SkiaHelper::isVCLSkiaEnabled()
+{
+    /**
+     * The !bSet part should only be called once! Changing the results in the same
+     * run will mix Skia and normal rendering.
+     */
+
+    static bool bSet = false;
+    static bool bEnable = false;
+    static bool bForceSkia = false;
+
+    // No hardware rendering, so no Skia
+    // TODO SKIA
+    if (Application::IsBitmapRendering())
+        return false;
+
+    if (bSet)
+    {
+        return bForceSkia || bEnable;
+    }
+
+    /*
+     * There are a number of cases that these environment variables cover:
+     *  * SAL_FORCESKIA forces Skia independent of any other option
+     *  * SAL_DISABLESKIA avoids the use of Skia if SAL_FORCESKIA is not set
+     */
+
+    bSet = true;
+    bForceSkia = !!getenv(
+        "SAL_FORCESKIA"); // TODO SKIA || officecfg::Office::Common::VCL::ForceOpenGL::get();
+
+    bool bRet = false;
+    bool bSupportsVCLSkia = true; // TODO SKIA supportsVCLOpenGL();
+    // TODO SKIA always call supportsVCLOpenGL to de-zombie the glxtest child process on X11
+    if (bForceSkia)
+    {
+        bRet = true;
+    }
+    else if (bSupportsVCLSkia)
+    {
+        static bool bEnableSkiaEnv = !!getenv("SAL_ENABLESKIA");
+
+        bEnable = bEnableSkiaEnv;
+
+        // TODO SKIA        if (officecfg::Office::Common::VCL::UseOpenGL::get())
+
+        // Force disable in safe mode
+        if (Application::IsSafeModeEnabled())
+            bEnable = false;
+
+        bRet = bEnable;
+    }
+
+    // TODO SKIA    CrashReporter::AddKeyValue("UseOpenGL", OUString::boolean(bRet));
+
+    return bRet;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */