feat: add camera viewport rect render areas

engine/src/Components/CameraComponent.cpp

@@ -25,6 +25,16 @@ void CameraComponent::SetFarClipPlane(float value) {
     m_farClipPlane = std::max(m_nearClipPlane + 0.001f, value);
 }
 
+void CameraComponent::SetViewportRect(const Math::Rect& value) {
+    const float x = std::clamp(value.x, 0.0f, 1.0f);
+    const float y = std::clamp(value.y, 0.0f, 1.0f);
+    const float width = std::clamp(value.width, 0.0f, 1.0f);
+    const float height = std::clamp(value.height, 0.0f, 1.0f);
+    const float right = std::min(1.0f, x + width);
+    const float bottom = std::min(1.0f, y + height);
+    m_viewportRect = Math::Rect(x, y, right - x, bottom - y);
+}
+
 void CameraComponent::Serialize(std::ostream& os) const {
     os << "projection=" << static_cast<int>(m_projectionType) << ";";
     os << "fov=" << m_fieldOfView << ";";
@@ -35,6 +45,7 @@ void CameraComponent::Serialize(std::ostream& os) const {
     os << "primary=" << (m_primary ? 1 : 0) << ";";
     os << "clearMode=" << static_cast<int>(m_clearMode) << ";";
     os << "cullingMask=" << m_cullingMask << ";";
+    os << "viewportRect=" << m_viewportRect.x << "," << m_viewportRect.y << "," << m_viewportRect.width << "," << m_viewportRect.height << ";";
     os << "clearColor=" << m_clearColor.r << "," << m_clearColor.g << "," << m_clearColor.b << "," << m_clearColor.a << ";";
 }
 
@@ -71,6 +82,12 @@ void CameraComponent::Deserialize(std::istream& is) {
             m_clearMode = static_cast<CameraClearMode>(std::stoi(value));
         } else if (key == "cullingMask") {
             m_cullingMask = static_cast<uint32_t>(std::stoul(value));
+        } else if (key == "viewportRect") {
+            std::replace(value.begin(), value.end(), ',', ' ');
+            std::istringstream ss(value);
+            Math::Rect viewportRect;
+            ss >> viewportRect.x >> viewportRect.y >> viewportRect.width >> viewportRect.height;
+            SetViewportRect(viewportRect);
         } else if (key == "clearColor") {
             std::replace(value.begin(), value.end(), ',', ' ');
             std::istringstream ss(value);