From efd358d734c78d4608906c2a5dc9210b72db4db2 Mon Sep 17 00:00:00 2001
From: whitequark <whitequark@whitequark.org>
Date: Sat, 13 Aug 2016 09:55:37 +0000
Subject: [PATCH] Unbreak PNG export.

Before this commit, on Win32 the toolbar was visible, and
the framebuffer was flipped, whereas on other platforms just a black
image was exported.
---
 src/export.cpp | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/export.cpp b/src/export.cpp
index 8990080..386d262 100644
--- a/src/export.cpp
+++ b/src/export.cpp
@@ -1089,6 +1089,11 @@ void SolveSpaceUI::ExportMeshAsThreeJsTo(FILE *f, const std::string &filename,
 //-----------------------------------------------------------------------------
 void SolveSpaceUI::ExportAsPngTo(const std::string &filename) {
 #if !defined(HEADLESS)
+    // Somewhat hacky way to invoke glReadPixels without dragging in all OpenGL headers.
+    OpenGl1Renderer canvas = {};
+    canvas.camera = SS.GW.GetCamera();
+    std::shared_ptr<Pixmap> screenshot;
+
     // No guarantee that the back buffer contains anything valid right now,
     // so repaint the scene. And hide the toolbar too.
     bool prevShowToolbar = SS.showToolbar;
@@ -1097,17 +1102,22 @@ void SolveSpaceUI::ExportAsPngTo(const std::string &filename) {
     GlOffscreen offscreen;
     offscreen.Render((int)SS.GW.width, (int)SS.GW.height, [&] {
         SS.GW.Paint();
+        screenshot = canvas.ReadFrame();
     });
+#else
+    SS.GW.Paint();
+    screenshot = canvas.ReadFrame();
 #endif
     SS.showToolbar = prevShowToolbar;
 
-    // Somewhat hacky way to invoke glReadPixels without dragging in all OpenGL headers.
-    OpenGl1Renderer canvas = {};
-    canvas.camera = SS.GW.GetCamera();
-    std::shared_ptr<Pixmap> screenshot = canvas.ReadFrame();
+#if defined(WIN32) || defined(HAVE_GTK)
+    bool flip = true;
+#else
+    bool flip = false;
+#endif
 
     FILE *f = ssfopen(filename, "wb");
-    if(!f || !screenshot->WritePng(f, /*flip=*/FLIP_FRAMEBUFFER)) {
+    if(!f || !screenshot->WritePng(f, flip)) {
         Error("Couldn't write to '%s'", filename.c_str());
     }
     if(f) fclose(f);