smartin3d

Modest 3D game engine, written only for educational purposes.

Currently, this project runs on Windows, but may also be built for Linux and Mac OS if the required libraries exist on the system. It requires GLEW, GLFW, GLM, assimp. Paths to these libraries can be set manually as command line arguments to cmake, i.e. cmake . -DGLEW_ROOT=... -DGLFW32_ROOT=... -DGLM_ROOT=... -DASSIMP_ROOT=....

Code snippets

App creation

Simply create an App object, put the application name and windows size in the constructor, and call the Init() method.

smartin::base::App app("App name", 1280, 720);
app.Init();

Actor creation

Put the name of the actor and (optionally) position, size, and rotation (in Euler angles) of the actor.

smartin::utils::CreateActor("actor",
                            vec3(-8.0f, 2.0f, 5.0f),
                            vec3(0.4f, 0.4f, 0.4f),
                            vec3(-90.0f, 0.0f, 0.0f));

Camera creation

Put position, rotation in Euler angles, and field of view.

app.CreateCamera(vec3(0.0f, 0.0f, 0.0f), vec3(0.0f, -60.0f, 0.0f), 45.0f);

Loading actor from file

Put the name of the actor, the name of a 3D model file located in the "assets/models" subdirectory, and (optionally) position, size, and rotation (in Euler angles) of the actor.

smartin::utils::CreateActorWithAppearance("cone", "cone.obj",
                                          vec3(-8.0f, 2.0f, 5.0f),
                                          vec3(0.4f, 0.4f, 0.4f),
                                          vec3(-90.0f, 0.0f, 0.0f));

or just

app.AddActor("cone", "cone.obj",
             vec3(-8.0f, 2.0f, 5.0f),
             vec3(0.4f, 0.4f, 0.4f),
             vec3(-90.0f, 0.0f, 0.0f));

Search over actors and assets

auto cone = smartin::utils::FindActor("cone");

auto material = smartin::utils::GetMaterial("cone_mat");

Actor destroyment

smartin::utils::DestroyActor(smartin::utils::FindActor("cone"));

Loading skybox

Put names of 6 skybox textures located in the "assets/textures/skyboxes" subdirectory.

app.SetSkybox({
  "skybox_rt.tga",
  "skybox_lf.tga",
  "skybox_up.tga",
  "skybox_dn.tga",
  "skybox_bk.tga",
  "skybox_ft.tga"
});

Setting target FPS

app.SetTargetFPS(120);

Job description

Create a job class inherited from the base::Job, override Tick() method called every frame before rendering pass.

class CameraMovementJob : public smartin::base::Job

Job registration

Put an instance of the custom job to the application.

app.AddJob<CameraMovementJob>(app.GetCamera(), 10.0f, 1.0f);

Start application

app.Run();

Getting delta time

auto dt = smartin::utils::time::GetDeltaTime();

Checking if key is pressed

if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::space))

Checking if key was pressed down on current frame

if (smartin::utils::input::keyboard::IsKeyDown(smartin::utils::input::space))

Checking if key was released on current frame

if (smartin::utils::input::keyboard::IsKeyUp(smartin::utils::input::space))

Job example

This job processes the input and provides camera movement.

class CameraMovementJob : public smartin::base::Job {
public:
    CameraMovementJob(shared_ptr<smartin::base::Camera> camera, float _speed, float _turnSpeed) :
        cameraTransform(camera->GetTransform()),
        speed(_speed),
        turnSpeed(_turnSpeed) { }

    void Tick() override {
        vec3 forward = cameraTransform->GetForward();
        vec3 right = cameraTransform->GetRight();
        vec3 up = cameraTransform->GetUp();

        // Keys
        vec3 direction = vec3(0.0f, 0.0f, 0.0f);

        if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::w))
            direction += forward;
        if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::s))
            direction -= forward;

        if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::a))
            direction += right;
        if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::d))
            direction -= right;

        if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::r))
            direction += up;
        if (smartin::utils::input::keyboard::IsKey(smartin::utils::input::w))
            direction -= up;

        direction = smartin::utils::time::GetDeltaTime() * speed * normalize(direction);
        cameraTransform->Move(direction);

        // Mouse
        vec2 mouseDelta = smartin::utils::input::mouse::GetCursorDelta();
        mouseDelta *= turnSpeed;

        float yaw = -mouseDelta.x;
        float pitch = mouseDelta.y;
        if (pitch > 89.0f)
            pitch = 89.0f;
        else if (pitch < -89.0f)
            pitch = -89.0f;

        cameraTransform->Rotate(vec3(pitch, yaw, 0.0f));
    }

private:
    shared_ptr<smartin::base::Transform> cameraTransform;
    float speed, turnSpeed;
};

main() example

int main() {
    smartin::base::App app("App name", 1280, 720);
    app.Init();
    app.SetTargetFPS(120);

    auto camera = app.CreateCamera(vec3(0.0f, 0.0f, 0.0f), vec3(0.0f, -60.0f, 0.0f));
    app.SetSkybox({
      "skybox_rt.tga",
      "skybox_lf.tga",
      "skybox_up.tga",
      "skybox_dn.tga",
      "skybox_bk.tga",
      "skybox_ft.tga"
    });

    app.AddActor("xwing", "x-wing.obj",
                 vec3(-7.0f, 0.0f, 10.0f),
                 vec3(0.006f, 0.006f, 0.006f));
    app.AddActor("cone", "cone.obj",
                 vec3(-8.0f, 2.0f, 5.0f));

    app.AddJob<CameraMovementJob>(camera, 10.0f, 1.0f);

    app.Run();
}