patch ImGui so it supports square textures

in the font atlas

src/gui/render/abstract.cpp

@@ -105,6 +105,10 @@ bool FurnaceGUIRender::supportsDrawOsc() {
   return false;
 }
 
+bool FurnaceGUIRender::areTexturesSquare() {
+  return false;
+}
+
 int FurnaceGUIRender::getWindowFlags() {
   return 0;
 }

src/gui/render/renderDX9.cpp

@@ -469,6 +469,11 @@ void FurnaceGUIRenderDX9::setSwapInterval(int swapInt) {
   swapInterval=swapInt;
 }
 
+// I would use caps but...
+bool FurnaceGUIRenderDX9::areTexturesSquare() {
+  return true;
+}
+
 void FurnaceGUIRenderDX9::preInit(const DivConfig& conf) {
 }
 

src/gui/render/renderDX9.h

@@ -59,6 +59,7 @@ class FurnaceGUIRenderDX9: public FurnaceGUIRender {
     void clear(ImVec4 color);
     bool newFrame();
     bool canVSync();
+    bool areTexturesSquare();
     void createFontsTexture();
     void destroyFontsTexture();
     void renderGUI();

src/gui/render/renderGL1.cpp

@@ -225,6 +225,10 @@ int FurnaceGUIRenderGL1::getWindowFlags() {
   return SDL_WINDOW_OPENGL;
 }
 
+bool FurnaceGUIRenderGL1::areTexturesSquare() {
+  return true;
+}
+
 int FurnaceGUIRenderGL1::getMaxTextureWidth() {
   return maxWidth;
 }

src/gui/render/renderGL1.h

@@ -43,6 +43,7 @@ class FurnaceGUIRenderGL1: public FurnaceGUIRender {
     void clear(ImVec4 color);
     bool newFrame();
     bool canVSync();
+    bool areTexturesSquare();
     void createFontsTexture();
     void destroyFontsTexture();
     void renderGUI();