From 743fc9dbd0fede7dc89f784a4f6fcae46ef856d1 Mon Sep 17 00:00:00 2001
From: bubnikv <bubnikv@gmail.com>
Date: Mon, 11 Dec 2017 18:00:51 +0100
Subject: [PATCH] Workaround for buggy Intel HD Graphics OpenGL drivers: Fall
 back to OpenGL 1.1 by a "use_legacy_opengl" preferences switch.
 https://github.com/prusa3d/Slic3r/issues/233
 https://github.com/prusa3d/Slic3r/issues/268
 https://github.com/prusa3d/Slic3r/issues/619

---
 lib/Slic3r/GUI/3DScene.pm       | 12 +++++++++++-
 lib/Slic3r/GUI/Preferences.pm   | 10 +++++++++-
 xs/src/slic3r/GUI/AppConfig.cpp |  4 ++++
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/lib/Slic3r/GUI/3DScene.pm b/lib/Slic3r/GUI/3DScene.pm
index 51c822590eb..7fae4894a9a 100644
--- a/lib/Slic3r/GUI/3DScene.pm
+++ b/lib/Slic3r/GUI/3DScene.pm
@@ -15,7 +15,7 @@ package Slic3r::GUI::3DScene::Base;
 use strict;
 use warnings;
 
-use Wx qw(:timer :bitmap :icon :dialog);
+use Wx qw(wxTheApp :timer :bitmap :icon :dialog);
 use Wx::Event qw(EVT_PAINT EVT_SIZE EVT_ERASE_BACKGROUND EVT_IDLE EVT_MOUSEWHEEL EVT_MOUSE_EVENTS EVT_CHAR EVT_TIMER);
 # must load OpenGL *before* Wx::GLCanvas
 use OpenGL qw(:glconstants :glfunctions :glufunctions :gluconstants);
@@ -956,6 +956,16 @@ sub UseVBOs {
     my ($self) = @_;
 
     if (! defined ($self->{use_VBOs})) {
+        my $use_legacy = wxTheApp->{app_config}->get('use_legacy_opengl');
+        if ($use_legacy eq '1') {
+            # Disable OpenGL 2.0 rendering.
+            $self->{use_VBOs} = 0;
+            # Don't enable the layer editing tool.
+            $self->{layer_editing_enabled} = 0;
+            # 2 means failed
+            $self->{layer_editing_initialized} = 2;
+            return 0;
+        }
         # This is a special path for wxWidgets on GTK, where an OpenGL context is initialized
         # first when an OpenGL widget is shown for the first time. How ugly.
         return 0 if (! $self->init && $^O eq 'linux');
diff --git a/lib/Slic3r/GUI/Preferences.pm b/lib/Slic3r/GUI/Preferences.pm
index d20ccb53fd8..0f0f319fe9c 100644
--- a/lib/Slic3r/GUI/Preferences.pm
+++ b/lib/Slic3r/GUI/Preferences.pm
@@ -72,6 +72,13 @@ sub new {
                        'if they are marked as incompatible with the active printer',
         default     => $app_config->get("show_incompatible_presets"),
     ));
+    $optgroup->append_single_option_line(Slic3r::GUI::OptionsGroup::Option->new(
+        opt_id      => 'use_legacy_opengl',
+        type        => 'bool',
+        label       => 'Use legacy OpenGL 1.1 rendering',
+        tooltip     => 'If you have rendering issues caused by a buggy OpenGL 2.0 driver, you may try to check this checkbox. This will disable the layer height editing, so it is likely better to upgrade your graphics driver.',
+        default     => $app_config->get("use_legacy_opengl"),
+    ));
     
     my $sizer = Wx::BoxSizer->new(wxVERTICAL);
     $sizer->Add($optgroup->sizer, 0, wxEXPAND | wxBOTTOM | wxLEFT | wxRIGHT, 10);
@@ -90,7 +97,8 @@ sub _accept {
     my ($self) = @_;
     
     if (defined($self->{values}{no_controller}) ||
-        defined($self->{values}{no_defaults})) {
+        defined($self->{values}{no_defaults}) ||
+        defined($self->{values}{use_legacy_opengl})) {
         Slic3r::GUI::warning_catcher($self)->("You need to restart Slic3r to make the changes effective.");
     }
     
diff --git a/xs/src/slic3r/GUI/AppConfig.cpp b/xs/src/slic3r/GUI/AppConfig.cpp
index 3161c5b788e..9378a209427 100644
--- a/xs/src/slic3r/GUI/AppConfig.cpp
+++ b/xs/src/slic3r/GUI/AppConfig.cpp
@@ -45,6 +45,10 @@ void AppConfig::set_defaults()
     // Version check is enabled by default in the config, but it is not implemented yet.
     if (get("version_check").empty())
         set("version_check", "1");
+    // Use OpenGL 1.1 even if OpenGL 2.0 is available. This is mainly to support some buggy Intel HD Graphics drivers.
+    // https://github.com/prusa3d/Slic3r/issues/233
+    if (get("use_legacy_opengl").empty())
+        set("use_legacy_opengl", "0");
 }
 
 void AppConfig::load()