requestFloatBuffer option

src/hello_imgui/internal/backend_impls/rendering_metal.mm

@@ -4,9 +4,26 @@
 #include <backends/imgui_impl_metal.h>
 #include "hello_imgui/hello_imgui.h"
 
+#import <Cocoa/Cocoa.h>
 
 namespace HelloImGui
 {
+    bool hasEdrSupport()
+    {
+        NSArray<NSScreen *> * screens = [NSScreen screens];
+        bool buffer_edr = false;
+
+        for (NSScreen * screen in screens) {
+            if ([screen respondsToSelector:@selector
+                        (maximumPotentialExtendedDynamicRangeColorComponentValue)]) {
+                if ([screen maximumPotentialExtendedDynamicRangeColorComponentValue] >= 2.f)
+                    buffer_edr = true;
+            }
+        }
+
+        return buffer_edr;
+    }
+
     MetalGlobals& GetMetalGlobals()
     {
         static MetalGlobals sMetalGlobals;

src/hello_imgui/internal/backend_impls/rendering_metal_glfw.mm

@@ -44,7 +44,7 @@ void PrepareGlfwForMetal(GLFWwindow* glfwWindow, const RendererBackendOptions& r
             gMetalGlobals.caMetalLayer = [CAMetalLayer layer];
             gMetalGlobals.caMetalLayer.device = gMetalGlobals.mtlDevice;
 
-            if (rendererBackendOptions.metalOptions.fixmeDummyOptionName)
+            if (rendererBackendOptions.requestFloatBuffer)
             {
                 gMetalGlobals.caMetalLayer.pixelFormat = MTLPixelFormatRGBA16Float;
                 gMetalGlobals.caMetalLayer.wantsExtendedDynamicRangeContent = YES;

src/hello_imgui/internal/backend_impls/rendering_metal_sdl.mm

@@ -42,7 +42,7 @@ void PrepareSdlForMetal(SDL_Window* sdlWindow, const RendererBackendOptions& ren
             // Setup Platform/Renderer backends
             gMetalGlobals.caMetalLayer = (__bridge CAMetalLayer*)SDL_RenderGetMetalLayer(gSdlMetalGlobals.sdlRenderer);
 
-            if (rendererBackendOptions.metalOptions.fixmeDummyOptionName)
+            if (rendererBackendOptions.requestFloatBuffer)
             {
                 gMetalGlobals.caMetalLayer.pixelFormat = MTLPixelFormatRGBA16Float;
                 gMetalGlobals.caMetalLayer.wantsExtendedDynamicRangeContent = YES;

src/hello_imgui/renderer_backend_options.cpp

@@ -0,0 +1,11 @@
+#include "renderer_backend_options.h"
+
+namespace HelloImGui
+{
+
+// currently, only the metal backend has support for this
+#ifndef HELLOIMGUI_HAS_METAL
+bool hasEdrSupport() { return false; }
+#endif
+
+}  // namespace HelloImGui

src/hello_imgui/renderer_backend_options.h

@@ -1,19 +1,27 @@
 #pragma once
 
-
 namespace HelloImGui
 {
+
 /**
- @@md#RendererBackendOptions
+    Check whether extended dynamic range (EDR), i.e. the ability to reproduce intensities exceeding the
+    standard dynamic range from 0.0-1.0, is supported.
 
-**RendererBackendOptions** is a struct that contains options for the renderer backend (Metal, Vulkan, DirectX, ...).
- Members:
-* `metalOptions`: _MetalOptions_. Options for the Metal backend (only filled if the Metal backend is available)
+    To leverage EDR support, you will need to set `floatBuffer=true` in `RendererBackendOptions`.
+    Only the macOS Metal backend currently supports this.
 
+    \return This currently returns false on all backends except Metal, where it checks whether this is
+    supported on the current displays.
+*/
+bool hasEdrSupport();
+
+/**
+ @@md#RendererBackendOptions
 
-**MetalOptions** is a struct that contains options for the Metal backend.
- Members:
-* `fixmeDummyOptionName`: _bool, default=false_. Dummy option for Metal backend (to be completed)
+**RendererBackendOptions** is a struct that contains options for the renderer backend (Metal, Vulkan, DirectX,
+...). Members:
+* `requestFloatBuffer`: _bool, default=false_. Set to true to request a floating-point framebuffer.
+        Before setting this to true, first check `hasEdrSupport`
 
 
 Note: If using the Metal, Vulkan or DirectX rendering backend, you can find some interesting pointers inside
@@ -25,20 +33,10 @@ Note: If using the Metal, Vulkan or DirectX rendering backend, you can find some
 @@md
 */
 
-
-#ifdef HELLOIMGUI_HAS_METAL
-struct MetalOptions
-{
-    // to be completed
-    bool fixmeDummyOptionName = false;
-};
-#endif
-
 struct RendererBackendOptions
 {
-#ifdef HELLOIMGUI_HAS_METAL
-    MetalOptions metalOptions;
-#endif
+
+    bool requestFloatBuffer = false;
 };
 
-} // namespace HelloImGui
+}  // namespace HelloImGui

src/hello_imgui_demos/hello_imgui_demodocking/hello_imgui_demodocking.main.cpp

@@ -13,6 +13,7 @@ It demonstrates how to:
 */
 
 #include "hello_imgui/hello_imgui.h"
+#include "hello_imgui/renderer_backend_options.h"
 #include "imgui.h"
 #include "misc/cpp/imgui_stdlib.h"
 #include "imgui_internal.h"
@@ -629,6 +630,13 @@ int main(int, char**)
     runnerParams.appWindowParams.borderlessResizable = true;
     runnerParams.appWindowParams.borderlessClosable = true;
 
+    // test EDR support on macOS/Metal
+    bool requestEDR = HelloImGui::hasEdrSupport();
+    runnerParams.rendererBackendOptions.requestFloatBuffer = requestEDR;
+    HelloImGui::Log(HelloImGui::LogLevel::Info,
+                    "Creating a %s framebuffer.",
+                    requestEDR ? "floating-point precision" : "standard precision");
+
     // Load additional font
     runnerParams.callbacks.LoadAdditionalFonts = [&appState]() { LoadFonts(appState); };