From 7520986e97ac742ec634bfab102ecc82e21d81cb Mon Sep 17 00:00:00 2001
From: Jakub Domagala <domagala.jacob@gmail.com>
Date: Wed, 31 Jan 2024 22:40:36 +0100
Subject: [PATCH] [#187]: Don't recalculate ViewProjection matrix when not
 needed

---
 editor/editor.cpp                 |  2 +-
 engine/renderer/camera/camera.cpp | 22 ++++++++++++----------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/editor/editor.cpp b/editor/editor.cpp
index 74921512..ce99140e 100644
--- a/editor/editor.cpp
+++ b/editor/editor.cpp
@@ -748,7 +748,7 @@ Editor::GetObjectsInArea(const std::array< glm::vec2, 4 >& area) const
 {
    std::set< Object::ID > objectsList = {};
 
-   if (glm::length(area.at(1) - area.at(3)) < currentLevel_->GetTileSize() / 2)
+   if (glm::length(area.at(1) - area.at(3)) < currentLevel_->GetTileSize() / 2.0f)
    {
       return {};
    }
diff --git a/engine/renderer/camera/camera.cpp b/engine/renderer/camera/camera.cpp
index a8661936..611080c9 100644
--- a/engine/renderer/camera/camera.cpp
+++ b/engine/renderer/camera/camera.cpp
@@ -89,19 +89,21 @@ Camera::Rotate(float angle, bool cumulative)
 void
 Camera::Zoom(float value)
 {
-   m_zoomScale += value * m_zoomSpeed;
+   const auto oldZoom = m_zoomScale; 
+   m_zoomScale = glm::clamp(m_zoomScale + (value * m_zoomSpeed), m_maxZoomOut, m_maxZoomIn);
 
-   m_zoomScale = glm::clamp(m_zoomScale, m_maxZoomOut, m_maxZoomIn);
-
-   const auto left = -m_windowSize.x / (2.0f + m_zoomScale);
-   const auto right = m_windowSize.x / (2.0f + m_zoomScale);
-   const auto top = m_windowSize.y / (2.0f + m_zoomScale);
-   const auto bottom = -m_windowSize.y / (2.0f + m_zoomScale);
+   if (oldZoom != m_zoomScale)
+   {
+      const auto left = -m_windowSize.x / (2.0f + m_zoomScale);
+      const auto right = m_windowSize.x / (2.0f + m_zoomScale);
+      const auto top = m_windowSize.y / (2.0f + m_zoomScale);
+      const auto bottom = -m_windowSize.y / (2.0f + m_zoomScale);
 
-   // NOLINTNEXTLINE top and bottom swapped intentionally
-   m_projectionMatrix = glm::ortho(left, right, top, bottom, nearPlane_, farPlane_);
+      // NOLINTNEXTLINE top and bottom swapped intentionally
+      m_projectionMatrix = glm::ortho(left, right, top, bottom, nearPlane_, farPlane_);
 
-   m_viewProjectionMatrix = m_projectionMatrix * m_viewMatrix;
+      m_viewProjectionMatrix = m_projectionMatrix * m_viewMatrix;
+   }
 }
 
 float