From abdd7137abcebeca64b532fdc8c2b636f5d52f57 Mon Sep 17 00:00:00 2001
From: Anish Bhobe <anishbhobe@hotmail.com>
Date: Wed, 24 Jul 2024 22:06:01 +0200
Subject: [PATCH] Improved Resolution handling.

---
 samples/03_model_render/model_render.cpp | 61 ++++++++++++++++--------
 1 file changed, 41 insertions(+), 20 deletions(-)

diff --git a/samples/03_model_render/model_render.cpp b/samples/03_model_render/model_render.cpp
index 4531309..ce54756 100644
--- a/samples/03_model_render/model_render.cpp
+++ b/samples/03_model_render/model_render.cpp
@@ -122,9 +122,9 @@ main(int, char **)
     Camera camera = {
         .m_View = lookAt(vec3(0.0f, 2.0f, 2.0f), vec3(0.0f), vec3(0.0f, 1.0f, 0.0f)),
         .m_Perspective = glm::perspective(
-            70_deg, Cast<f32>(internalResolution.width) / Cast<f32>(internalResolution.height), 0.1f, 100.0f),
+            70_deg, Cast<f32>(swapchain.m_Extent.width) / Cast<f32>(swapchain.m_Extent.height), 0.1f, 100.0f),
         .m_Position = vec4{0.0f, 2.0f, 2.0f, 1.0f},
-        .m_AspectRatio = Cast<f32>(internalResolution.width) / Cast<f32>(internalResolution.height),
+        .m_AspectRatio = Cast<f32>(swapchain.m_Extent.width) / Cast<f32>(swapchain.m_Extent.height),
     };
 
     UniformBuffer ubo;
@@ -273,7 +273,14 @@ main(int, char **)
     gui::Init(&context, &device, &window, swapchain.m_Format, Cast<u32>(swapchain.m_ImageViews.size()),
               queueAllocation.m_Family, commandQueue);
     bool rotating = false;
-    i32 currentInternalResolution[2] = {Cast<i32>(internalResolution.width), Cast<i32>(internalResolution.height)};
+    bool lockToScreen = true;
+    i32 height = Cast<i32>(internalResolution.height);
+    vk::Extent2D inputResolution = internalResolution;
+
+    swapchain.RegisterResizeCallback([&camera](vk::Extent2D extent) {
+        camera.m_AspectRatio = Cast<f32>(extent.width) / Cast<f32>(extent.height);
+        camera.m_Perspective = glm::perspective(70_deg, camera.m_AspectRatio, 0.1f, 100.0f);
+    });
 
     Time::Init();
 
@@ -285,31 +292,45 @@ main(int, char **)
         gui::StartBuild();
 
         gui::Begin("Settings");
-        gui::Text("Window Resolution: %udx%ud", swapchain.m_Extent.width, swapchain.m_Extent.height);
-        gui::Text("FrameBuffer Resolution %dx%d", currentInternalResolution[0], currentInternalResolution[1]);
-        gui::InputInt("FrameBuffer Height", &currentInternalResolution[1], 1, 10);
-
-        camera.m_AspectRatio = Cast<f32>(swapchain.m_Extent.width) / Cast<f32>(swapchain.m_Extent.height);
-        currentInternalResolution[0] = Cast<i32>(camera.m_AspectRatio * currentInternalResolution[1]);
-        for (i32 &val : currentInternalResolution)
+        gui::Text("Window Resolution: %ux%u", swapchain.m_Extent.width, swapchain.m_Extent.height);
+        gui::Text("FrameBuffer Resolution %ux%u", internalResolution.width, internalResolution.height);
+        gui::Checkbox("Lock Resolution to Window", &lockToScreen);
+        if (!lockToScreen)
         {
-            val = eastl::clamp(val, 64, 7680);
-        }
-        camera.m_Perspective = glm::perspective(70_deg, camera.m_AspectRatio, 0.1f, 100.0f);
-
-        if (gui::Button("Change Resolution"))
-        {
-            if (currentInternalResolution[0] != internalResolution.width ||
-                currentInternalResolution[1] != internalResolution.height)
+            if (gui::InputInt("FrameBuffer Height", &height, 1, 10))
             {
-                internalResolution =
-                    vk::Extent2D{}.setWidth(currentInternalResolution[0]).setHeight(currentInternalResolution[1]);
+                height = eastl::clamp(height, 64, 4320);
+            }
+
+            inputResolution.height = height;
+            inputResolution.width = Cast<i32>(camera.m_AspectRatio * Cast<f32>(inputResolution.height));
+
+            if (gui::Button("Change Resolution"))
+            {
+                if (inputResolution.width != internalResolution.width ||
+                    inputResolution.height != internalResolution.height)
+                {
+                    internalResolution = inputResolution;
+                    viewport.width = Cast<f32>(internalResolution.width);
+                    viewport.height = -Cast<f32>(internalResolution.height);
+                    viewport.y = Cast<f32>(internalResolution.height);
+                    scissor.extent = internalResolution;
+                }
+            }
+        }
+        else
+        {
+            if (swapchain.m_Extent.width != internalResolution.width ||
+                swapchain.m_Extent.height != internalResolution.height)
+            {
+                internalResolution = swapchain.m_Extent;
                 viewport.width = Cast<f32>(internalResolution.width);
                 viewport.height = -Cast<f32>(internalResolution.height);
                 viewport.y = Cast<f32>(internalResolution.height);
                 scissor.extent = internalResolution;
             }
         }
+        gui::Separator();
         gui::Text("Delta: %0.6f ms", 1000.0f * Time::m_Delta);
         gui::Text("FPS: %0.6f", 1.0f / Time::m_Delta);
         gui::Checkbox("Rotate", &rotating);