Add interface for software-only bitmap rendering

When SAL_USE_VCLPLUGIN=svp is used, LO is expected to render
output only to bitmaps, without real GUI windows. This adds an
enabler and a getter function to the Application class, so one
can query this information easy as (Enable|Is)BitmapRendering.

This can be used by all VCL plugins, which can't fall back to
the Cairo based SVP plugin, primary OSX and Win.

A working implementation should allow to run all test via SSH.
All window-requiring tests already have to set this requirement
using gb_CppunitTest_use_vcl_non_headless(_with_windows)? and
should be moved to a different make target, or we need some test
harness to handle this correctly, before VCL fails the test.

Change-Id: I4bd4c81122a6686b090fdd93256d4712ac5f05dd
Reviewed-on: https://gerrit.libreoffice.org/64051
Tested-by: Jenkins
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>

4 files changed, 20 insertions, 13 deletions

diff --git a/vcl/inc/svdata.hxx b/vcl/inc/svdata.hxx
index 21ca3567b56a..b83607f75c44 100644
--- a/vcl/inc/svdata.hxx
+++ b/vcl/inc/svdata.hxx
@@ -154,6 +154,7 @@ struct ImplSVAppData
     bool                    mbAppQuit = false;              // is Application::Quit() called
     bool                    mbSettingsInit = false;         // true: Settings are initialized
     DialogCancelMode meDialogCancel = DialogCancelMode::Off; // true: All Dialog::Execute() calls will be terminated immediately with return false
+    bool mbRenderToBitmaps = false; // set via svp / headless plugin
 
     /** Controls whether showing any IME status window is toggled on or off.
 
diff --git a/vcl/source/app/salplug.cxx b/vcl/source/app/salplug.cxx
index a79339cd0ad2..205f5dae0526 100644
--- a/vcl/source/app/salplug.cxx
+++ b/vcl/source/app/salplug.cxx
@@ -243,6 +243,13 @@ SalInstance *CreateSalInstance()
 #endif
         rtl::Bootstrap::get( "SAL_USE_VCLPLUGIN", aUsePlugin );
 
+    if (aUsePlugin == "svp")
+    {
+        Application::EnableBitmapRendering();
+#ifndef HEADLESS_VCLPLUG
+        aUsePlugin.clear();
+#endif
+    }
     if( !aUsePlugin.isEmpty() )
         pInst = tryInstance( aUsePlugin, true );
 
diff --git a/vcl/source/app/svapp.cxx b/vcl/source/app/svapp.cxx
index b42c1f158a9f..40ff79b7d70f 100644
--- a/vcl/source/app/svapp.cxx
+++ b/vcl/source/app/svapp.cxx
@@ -1438,6 +1438,7 @@ const LocaleDataWrapper& Application::GetAppLocaleDataWrapper()
 
 void Application::EnableHeadlessMode( bool dialogsAreFatal )
 {
+    assert(GetDialogCancelMode() == DialogCancelMode::Off);
     SetDialogCancelMode(
         dialogsAreFatal ? DialogCancelMode::Fatal : DialogCancelMode::Silent );
 }
@@ -1447,17 +1448,20 @@ bool Application::IsHeadlessModeEnabled()
     return IsDialogCancelEnabled() || comphelper::LibreOfficeKit::isActive();
 }
 
-static bool bConsoleOnly = false;
+void Application::EnableBitmapRendering()
+{
+    ImplGetSVData()->maAppData.mbRenderToBitmaps = true;
+}
 
-bool Application::IsConsoleOnly()
+bool Application::IsBitmapRendering()
 {
-    return bConsoleOnly;
+    return ImplGetSVData()->maAppData.mbRenderToBitmaps;
 }
 
 void Application::EnableConsoleOnly()
 {
     EnableHeadlessMode(true);
-    bConsoleOnly = true;
+    EnableBitmapRendering();
 }
 
 static bool bEventTestingMode = false;
diff --git a/vcl/source/opengl/OpenGLHelper.cxx b/vcl/source/opengl/OpenGLHelper.cxx
index 588ae70cabe0..882f35d424af 100644
--- a/vcl/source/opengl/OpenGLHelper.cxx
+++ b/vcl/source/opengl/OpenGLHelper.cxx
@@ -956,8 +956,8 @@ bool OpenGLHelper::isVCLOpenGLEnabled()
     static bool bEnable = false;
     static bool bForceOpenGL = false;
 
-    // If we are a console app, then we don't use OpenGL
-    if ( Application::IsConsoleOnly() )
+    // No hardware rendering, so no OpenGL
+    if (Application::IsBitmapRendering())
         return false;
 
     //tdf#106155, disable GL while loading certain bitmaps needed for the initial toplevel windows
@@ -988,19 +988,14 @@ bool OpenGLHelper::isVCLOpenGLEnabled()
     else if (bSupportsVCLOpenGL)
     {
         static bool bEnableGLEnv = !!getenv("SAL_ENABLEGL");
-        static bool bHeadlessPlugin = []{
-            OUString plugin;
-            rtl::Bootstrap::get("SAL_USE_VCLPLUGIN", plugin);
-            return plugin == "svp";
-        }();
 
         bEnable = bEnableGLEnv;
 
         if (officecfg::Office::Common::VCL::UseOpenGL::get())
             bEnable = true;
 
-        // Force disable in safe mode or when running with headless plugin
-        if (bHeadlessPlugin || Application::IsSafeModeEnabled())
+        // Force disable in safe mode
+        if (Application::IsSafeModeEnabled())
             bEnable = false;
 
         bRet = bEnable;