RenderNvgToFrameBuffer: improve antialias

pthom · Jan 11, 2024 · 72e5359 · 72e5359
1 parent 45ff68a
commit 72e5359
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Showing 2 changed files with 12 additions and 3 deletions.
diff --git a/bindings/imgui_bundle/demos_cpp/demos_nanovg/demo_nanovg_example_gl3.cpp b/bindings/imgui_bundle/demos_cpp/demos_nanovg/demo_nanovg_example_gl3.cpp
@@ -8,6 +8,8 @@
 
 #include "nanovg_demo/nanovg_demo.h"
 
+// On peut modifier CustomBackground durant l'execution
+
 
 struct MyNvgDemo
 {
@@ -64,9 +66,8 @@ int main(int, char**)
     {
         auto vg = ImmApp::NanoVGContext();
         appState.myNvgDemo = std::make_unique<MyNvgDemo>(vg);
-        float scale = ImGui::GetIO().DisplayFramebufferScale.x;
         int nvgImageFlags = 0; //NVG_IMAGE_FLIPY | NVG_IMAGE_PREMULTIPLIED;
-        appState.myFramebuffer = NvgImgui::CreateNvgFramebuffer(vg, (int)(1000 * scale), (int)(600 * scale), nvgImageFlags);
+        appState.myFramebuffer = NvgImgui::CreateNvgFramebuffer(vg, 1000, 600, nvgImageFlags);
     };
     runnerParams.callbacks.BeforeExit = [&]()
     {

diff --git a/external/nanovg/nvg_imgui/nvg_imgui.cpp b/external/nanovg/nvg_imgui/nvg_imgui.cpp
@@ -91,7 +91,15 @@ namespace NvgImgui
         if (clearColor.w > 0.f)
             FillClearColor(clearColor);
 
-        float pixelRatio = ImGui::GetIO().DisplayFramebufferScale.x;
+        // Note:
+        //    - internally, we use NVGLUframebuffer, provided by NanoVG
+        //    - NVGLUframebuffer does not handle pixelRatio
+        //    => using pixelRatio=DisplayFramebufferScale would lead to non anti-aliased rendering
+        //    => you may want to create texture of bigger size and scale down the drawing, in order to
+        //       improve the quality of the rendering
+
+        // float pixelRatio = ImGui::GetIO().DisplayFramebufferScale.x;
+        float pixelRatio = 1.f;
         nvgBeginFrame(vg, texture->Width, texture->Height, pixelRatio);
 
         // Flip the y-axis