From b410d8dc86933785822659ab51ace6aa222afc1f Mon Sep 17 00:00:00 2001
From: bsp2 <bs@tkscript.de>
Date: Thu, 25 Oct 2018 23:06:10 +0200
Subject: [PATCH] add "fbo" config option (settings.json) (for VirtualBox VM)

---
 include/global_ui.hpp             |  5 +++++
 src/settings.cpp                  | 21 ++++++++++++++++++---
 src/widgets/FramebufferWidget.cpp | 13 ++++++++++---
 vst2_bin/settings.json            |  3 ++-
 4 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/include/global_ui.hpp b/include/global_ui.hpp
index e13e516b..2d9c057b 100644
--- a/include/global_ui.hpp
+++ b/include/global_ui.hpp
@@ -104,6 +104,8 @@ struct GlobalUI {
       int placeholder_framecount;
    } param_info;
 
+   bool b_fbo;  // usually true. set to false when using the VirtualBox GL driver.
+   int pending_swap_interval; // -1=none, 1=vsync on, 0=vsync off
 
    void init(void) {
       
@@ -152,6 +154,9 @@ struct GlobalUI {
       param_info.tf_value = NULL;
       param_info.b_lock = false;
       param_info.placeholder_framecount = 0;
+
+      b_fbo = true;
+      pending_swap_interval = -1;
    } 
 
 };
diff --git a/src/settings.cpp b/src/settings.cpp
index 41c6ad62..7518099d 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -82,6 +82,10 @@ static json_t *settingsToJson() {
 	json_t *vsyncJ = json_boolean(vsync);
 	json_object_set_new(rootJ, "vsync", vsyncJ);
 
+   // fbo
+	json_t *fboJ = json_boolean(!global_ui->b_fbo);
+	json_object_set_new(rootJ, "fbo", fboJ);
+
    // touchInput
    int touchInput = lglw_touchinput_get(global_ui->window.lglw);
 	json_t *touchInputJ = json_boolean(touchInput);
@@ -252,12 +256,23 @@ static void settingsFromJson(json_t *rootJ, bool bWindowSizeOnly) {
       json_t *vsyncJ = json_object_get(rootJ, "vsync");
       if (vsyncJ)
       {
-         lglw_glcontext_push(global_ui->window.lglw);
-         lglw_swap_interval_set(global_ui->window.lglw, json_is_true(vsyncJ));
-         lglw_glcontext_pop(global_ui->window.lglw);
+         // lglw_glcontext_push(global_ui->window.lglw);
+         // lglw_swap_interval_set(global_ui->window.lglw, json_is_true(vsyncJ);
+         // lglw_glcontext_pop(global_ui->window.lglw);
+
+         // postpone until first vst2_editor_redraw() call (see window.cpp)
+         //  (note) on Linux we need a drawable to set the swap interval
+         global_ui->pending_swap_interval = json_is_true(vsyncJ);
       }
    }
 
+   // fbo support (not working with VirtualBox GL driver!)
+   json_t *fboJ = json_object_get(rootJ, "fbo");
+   if (fboJ)
+   {
+      global_ui->b_fbo = json_is_true(fboJ);
+   }
+
 	// allowCursorLock
 	json_t *allowCursorLockJ = json_object_get(rootJ, "allowCursorLock");
 	if (allowCursorLockJ)
diff --git a/src/widgets/FramebufferWidget.cpp b/src/widgets/FramebufferWidget.cpp
index 1f31a155..81d092ed 100644
--- a/src/widgets/FramebufferWidget.cpp
+++ b/src/widgets/FramebufferWidget.cpp
@@ -36,12 +36,19 @@ FramebufferWidget::~FramebufferWidget() {
 
 void FramebufferWidget::draw(NVGcontext *vg) {
 	// Bypass framebuffer rendering entirely
+   // printf("xxx FramebufferWidget::draw\n");
 #ifdef RACK_PLUGIN_SHARED
+   bool bFBO = false;
+#else
+   bool bFBO = global_ui->b_fbo;
+#endif // RACK_PLUGIN_SHARED
    // (note) FBO path crashes when plugin is a DLL (!)
    //         (the glGenFramebuffers() call in nvgluCreateFramebuffer() to be precise)
-   Widget::draw(vg);
-   return;
-#endif // RACK_PLUGIN_SHARED
+   if(!bFBO)
+   {
+      Widget::draw(vg);
+      return;
+   }
    // printf("xxx FramebufferWidget::draw: ENTER vg=%p\n", vg);
    // printf("xxx FramebufferWidget::draw: GetCurrentThreadId=%d\n", GetCurrentThreadId());
 
diff --git a/vst2_bin/settings.json b/vst2_bin/settings.json
index ed515ca7..e82ab5f9 100644
--- a/vst2_bin/settings.json
+++ b/vst2_bin/settings.json
@@ -13,6 +13,7 @@
   "zoom": 1.0,
   "refreshRate": 30,
   "vsync": true,
+  "fbo": true,
   "touchInput": false,
   "touchKbd": false,
   "oversampleFactor": 1.0,
@@ -265,4 +266,4 @@
   },
   "powerMeter": false,
   "checkVersion": true
-}
\ No newline at end of file
+}