Save and restore blend state when using nanovg

dgl/src/NanoVG.cpp

@@ -212,9 +212,24 @@ void NanoVG::endFrame()
 {
     DISTRHO_SAFE_ASSERT_RETURN(fInFrame,);
 
+    // Save current blend state
+    GLboolean blendEnabled;
+    GLint blendSrc, blendDst;
+    glGetBooleanv(GL_BLEND, &blendEnabled);
+    glGetIntegerv(GL_BLEND_SRC_ALPHA, &blendSrc);
+    glGetIntegerv(GL_BLEND_DST_ALPHA, &blendDst);
+
     if (fContext != nullptr)
         nvgEndFrame(fContext);
 
+    // Restore blend state
+    if (blendEnabled)
+        glEnable(GL_BLEND);
+    else
+        glDisable(GL_BLEND);
+
+    glBlendFunc(blendSrc, blendDst);
+
     fInFrame = false;
 }
 

dgl/src/nanovg/nanovg_gl.h

@@ -1138,7 +1138,7 @@ static void glnvg__renderFlush(void* uptr)
 		glBindVertexArray(0);
 #endif	
 		glDisable(GL_CULL_FACE);
-			glBindBuffer(GL_ARRAY_BUFFER, 0);
+		glBindBuffer(GL_ARRAY_BUFFER, 0);
 		glUseProgram(0);
 		glnvg__bindTexture(gl, 0);
 	}