Custom element registration

src/elements/health_bar_element.cpp

@@ -0,0 +1,51 @@
+#include "health_bar_element.hpp"
+#include <RmlUi/Core/Factory.h>
+#include <RmlUi/Core/ID.h>
+#include <RmlUi/Core/Math.h>
+#include <RmlUi/Core/Property.h>
+#include <RmlUi/Core/Types.h>
+#include <RmlUi/Core/Unit.h>
+
+HealthBarElement::HealthBarElement(const Rml::String& tag) : Rml::Element(tag) {
+    Rml::XMLAttributes attributes;
+
+    Rml::ElementPtr track = Rml::Factory::InstanceElement(this, "div", "div", attributes);
+    track->SetClass("healthbar-track", true);
+
+    Rml::ElementPtr fillElement = Rml::Factory::InstanceElement(this, "div", "div", attributes);
+    fillElement->SetClass("healthbar-fill", true);
+    fill = fillElement.get();
+
+    track->AppendChild(std::move(fillElement));
+    AppendChild(std::move(track));
+
+    UpdateFill();
+}
+
+void HealthBarElement::OnAttributeChange(const Rml::ElementAttributes &changed_attributes) {
+    Rml::Element::OnAttributeChange(changed_attributes);
+    if (changed_attributes.find("current") != changed_attributes.end() ||
+        changed_attributes.find("max") != changed_attributes.end()) {
+        UpdateFill();
+    }
+}
+
+void HealthBarElement::UpdateFill() {
+    int current = GetAttribute<int>("current", 0);
+    int max = GetAttribute<int>("max", 100);
+    if (max <= 0) max = 1;
+
+    float pct = Rml::Math::Clamp(static_cast<float>(current) / static_cast<float>(max), 0.0f, 1.0f) * 100.0f;
+
+    if (fill) {
+        fill->SetProperty(Rml::PropertyId::Width, Rml::Property(pct, Rml::Unit::PERCENT));
+
+        if (current >= 90) {
+            fill->SetProperty(Rml::PropertyId::BackgroundColor, Rml::Property("#33cc33", Rml::Unit::COLOUR));
+        } else if (current >= 50) {
+            fill->SetProperty(Rml::PropertyId::BackgroundColor, Rml::Property("#cccc33", Rml::Unit::COLOUR));
+        } else if (current >= 0) {
+            fill->SetProperty(Rml::PropertyId::BackgroundColor, Rml::Property("#cc3333", Rml::Unit::COLOUR));
+        }
+    }
+}

src/elements/health_bar_element.hpp

@@ -0,0 +1,14 @@
+#pragma once
+#include <RmlUi/Core/Element.h>
+#include <RmlUi/Core/Types.h>
+
+class HealthBarElement : public Rml::Element {
+public:
+    explicit HealthBarElement(const Rml::String& tag);
+
+    void OnAttributeChange(const Rml::ElementAttributes &changed_attributes) override;
+
+private:
+    void UpdateFill();
+    Rml::Element* fill = nullptr;
+};