feat: add more collider types + camera snapping fix

destrum/src/Components/MeshRendererComponent.cpp

@@ -1,6 +1,7 @@
 #include <destrum/Components/MeshRendererComponent.h>
 #include <destrum/Assets/AssetDatabase.h>
 #include <destrum/Assets/AssetReference.h>
+#include <destrum/Components/Physics/MeshShapeCollider.h>
 #include <destrum/Serialization/MaterialSerialization.h>
 #include <destrum/Graphics/GfxDevice.h>
 #include <destrum/Graphics/Resources/PrimitiveMeshes.h>
@@ -254,6 +255,9 @@ void MeshRendererComponent::SetMeshID(MeshID id) {
             meshKey = resources->meshes().getMeshKey(id);
         }
     }
+    if (GetGameObject()->GetComponent<MeshShapeCollider>() != nullptr) {
+        NotifyPhysicsChanged();
+    }
 }
 
 void MeshRendererComponent::SetMaterialID(MaterialID id) {

destrum/src/Components/Physics/ConvexHullCollider.cpp

@@ -0,0 +1,29 @@
+#include <destrum/Components/Physics/ConvexHullCollider.h>
+
+#include <imgui.h>
+
+nlohmann::json ConvexHullCollider::Serialize() const {
+    auto data = SerializeCollider();
+    data["maxVertices"] = m_MaxVertices;
+    return data;
+}
+
+void ConvexHullCollider::Deserialize(const nlohmann::json& data) {
+    DeserializeCollider(data);
+    if (data.contains("maxVertices")) {
+        SetMaxVertices(data.at("maxVertices").get<int>());
+    }
+}
+
+void ConvexHullCollider::DrawDebugLines(const glm::vec4& color) const {
+    DrawConvexHull(m_MaxVertices, color);
+}
+
+void ConvexHullCollider::ImGuiInspector() {
+    MeshShapeCollider::ImGuiInspector();
+
+    int maxVertices = m_MaxVertices;
+    if (ImGui::SliderInt("Max vertices", &maxVertices, MinVertices, MaxVertices)) {
+        SetMaxVertices(maxVertices);
+    }
+}

destrum/src/Components/Physics/CylinderCollider.cpp

@@ -0,0 +1,23 @@
+#include <destrum/Components/Physics/CylinderCollider.h>
+
+#include <destrum/Graphics/DebugDraw.h>
+
+#include <imgui.h>
+
+void CylinderCollider::DrawDebugLines(const glm::vec4& color) const {
+    DebugDraw::Cylinder(GetWorldCenter(), GetWorldRotation(), m_Radius, m_Height, color);
+}
+
+void CylinderCollider::ImGuiInspector() {
+    Collider::ImGuiInspector();
+
+    float radius = m_Radius;
+    if (ImGui::DragFloat("Radius", &radius, 0.05f, 0.0001f)) {
+        SetRadius(radius);
+    }
+
+    float height = m_Height;
+    if (ImGui::DragFloat("Height", &height, 0.05f, 0.0001f)) {
+        SetHeight(height);
+    }
+}

destrum/src/Components/Physics/MeshCollider.cpp

@@ -0,0 +1,43 @@
+#include <destrum/Components/Physics/MeshCollider.h>
+
+#include <imgui.h>
+
+#include <destrum/Components/Physics/Rigidbody.h>
+#include <destrum/Graphics/DebugDraw.h>
+#include <destrum/ObjectModel/GameObject.h>
+
+bool MeshCollider::UsesConvexFallback() const {
+    const auto* rigidbody = GetGameObject()->GetComponent<Rigidbody>();
+    return rigidbody != nullptr && rigidbody->GetType() == RigidbodyType::Dynamic;
+}
+
+PhysicsShapeDesc MeshCollider::BuildPhysicsShape() const {
+    if (UsesConvexFallback()) {
+        return BuildConvexHullShape(DynamicHullVertices);
+    }
+
+    auto source = GetSourceMesh();
+    if (!source || source->indices.empty()) {
+        return {};
+    }
+    return PhysicsShapeDesc::Mesh(std::move(source), GetShapeScale(), m_CenterOffset, m_IsTrigger);
+}
+
+void MeshCollider::DrawDebugLines(const glm::vec4& color) const {
+    if (UsesConvexFallback()) {
+        DrawConvexHull(DynamicHullVertices, color);
+        return;
+    }
+
+    if (const auto source = GetSourceMesh()) {
+        DebugDraw::Triangles(GetShapeMatrix(), source->points, source->indices, color);
+    }
+}
+
+void MeshCollider::ImGuiInspector() {
+    MeshShapeCollider::ImGuiInspector();
+
+    if (UsesConvexFallback()) {
+        ImGui::TextColored(ImVec4{1.0f, 0.6f, 0.2f, 1.0f}, "Dynamic rigidbody: using a convex hull");
+    }
+}

destrum/src/Components/Physics/MeshShapeCollider.cpp

@@ -0,0 +1,118 @@
+#include <destrum/Components/Physics/MeshShapeCollider.h>
+
+#include <cmath>
+#include <limits>
+
+#include <imgui.h>
+
+#include <glm/gtc/matrix_transform.hpp>
+
+#include <destrum/Components/MeshRendererComponent.h>
+#include <destrum/Graphics/DebugDraw.h>
+#include <destrum/Graphics/RenderResources.h>
+#include <destrum/Graphics/Renderer.h>
+#include <destrum/ObjectModel/GameObject.h>
+#include <destrum/ObjectModel/Transform.h>
+#include <destrum/Physics/PhysicsMeshCache.h>
+#include <destrum/Util/GameState.h>
+
+namespace {
+    struct Bounds {
+        glm::vec3 center{0.0f};
+        glm::vec3 halfExtents{0.0f};
+    };
+
+    Bounds ComputeBounds(const PhysicsMeshData& mesh) {
+        glm::vec3 min{std::numeric_limits<float>::max()};
+        glm::vec3 max{std::numeric_limits<float>::lowest()};
+        for (const glm::vec3& point : mesh.points) {
+            min = glm::min(min, point);
+            max = glm::max(max, point);
+        }
+        return {(min + max) * 0.5f, (max - min) * 0.5f};
+    }
+}
+
+std::shared_ptr<const PhysicsMeshData> MeshShapeCollider::GetSourceMesh() const {
+    if (m_CustomMesh) {
+        return m_CustomMesh;
+    }
+
+    const auto* meshRenderer = GetGameObject()->GetComponent<MeshRendererComponent>();
+    if (meshRenderer == nullptr || meshRenderer->GetMeshID() == NULL_MESH_ID || !GameState::GetInstance().HasRenderer()) {
+        return nullptr;
+    }
+
+    const RenderResources* resources = GameState::GetInstance().Renderer().getResources();
+    if (resources == nullptr || !resources->meshes().isValid(meshRenderer->GetMeshID())) {
+        return nullptr;
+    }
+
+    const MeshCache& meshes = resources->meshes();
+    return PhysicsMeshCache::FromCPUMesh(meshes.getMeshKey(meshRenderer->GetMeshID()),
+                                         meshes.getCPUMesh(meshRenderer->GetMeshID()));
+}
+
+glm::vec3 MeshShapeCollider::GetShapeScale() const {
+    glm::vec3 scale = GetTransform().GetWorldScale();
+    for (int axis = 0; axis < 3; ++axis) {
+        if (std::abs(scale[axis]) < 0.0001f) {
+            scale[axis] = scale[axis] < 0.0f ? -0.0001f : 0.0001f;
+        }
+    }
+    return scale;
+}
+
+glm::mat4 MeshShapeCollider::GetShapeMatrix() const {
+    return glm::translate(glm::mat4{1.0f}, GetWorldCenter()) *
+           glm::mat4_cast(GetWorldRotation()) *
+           glm::scale(glm::mat4{1.0f}, GetShapeScale());
+}
+
+PhysicsShapeDesc MeshShapeCollider::BuildConvexHullShape(int maxVertices) const {
+    const auto source = GetSourceMesh();
+    if (!source || source->points.empty()) {
+        return {};
+    }
+
+    const glm::vec3 scale = GetShapeScale();
+    if (auto hull = PhysicsMeshCache::ConvexHull(source, maxVertices)) {
+        return PhysicsShapeDesc::ConvexHull(std::move(hull), scale, m_CenterOffset, m_IsTrigger);
+    }
+
+    const Bounds bounds = ComputeBounds(*source);
+    return PhysicsShapeDesc::Box(glm::max(glm::abs(bounds.halfExtents * scale), glm::vec3{0.01f}),
+                                 m_CenterOffset + bounds.center * scale,
+                                 m_IsTrigger);
+}
+
+void MeshShapeCollider::DrawConvexHull(int maxVertices, const glm::vec4& color) const {
+    const auto source = GetSourceMesh();
+    if (!source || source->points.empty()) {
+        return;
+    }
+
+    if (const auto hull = PhysicsMeshCache::ConvexHull(source, maxVertices)) {
+        DebugDraw::Triangles(GetShapeMatrix(), hull->points, hull->indices, color);
+        return;
+    }
+
+    const Bounds bounds = ComputeBounds(*source);
+    const glm::vec3 scale = GetShapeScale();
+    DebugDraw::Box(GetWorldCenter() + GetWorldRotation() * (bounds.center * scale),
+                   GetWorldRotation(),
+                   glm::max(glm::abs(bounds.halfExtents * scale), glm::vec3{0.01f}),
+                   color);
+}
+
+void MeshShapeCollider::ImGuiInspector() {
+    Collider::ImGuiInspector();
+
+    if (m_CustomMesh) {
+        ImGui::TextDisabled("Custom mesh: %zu points", m_CustomMesh->points.size());
+    } else if (const auto source = GetSourceMesh()) {
+        ImGui::TextDisabled("Mesh: %zu vertices, %zu triangles", source->points.size(), source->indices.size() / 3);
+    } else {
+        ImGui::TextColored(ImVec4{1.0f, 0.6f, 0.2f, 1.0f}, "Needs a MeshRendererComponent with a mesh");
+    }
+}