gizmo.cxx

#include "gizmo.h"
 
#include <cgv/gui/mouse_event.h>
#include <cgv/math/ftransform.h>
#include <cgv/math/intersection.h>
 
using namespace cgv::render;
 
namespace cgv {
namespace app {
 
void gizmo::finish_frame(context& ctx) {
    if(!_view)
        _view = find_view_as_node();
 
    if(!_view)
        return;
 
    if(_geometry_out_of_date) {
        create_geometry();
        _geometry_out_of_date = false;
    }
    
    if(keep_screen_size_constant) {
        float adjusted_size = 0.3f * size_scale * static_cast<float>(_view->get_tan_of_half_of_fovy(true)) * dot(_position - _view->get_eye(), _view->get_view_dir());
 
        if(lock_size_during_interaction) {
            if(!_captured_mouse || _size < 0.0f)
                _size = adjusted_size;
        } else {
            _size = adjusted_size;
        }
    } else {
        _size = size_scale;
    }
 
    ctx.push_modelview_matrix();
    ctx.mul_modelview_matrix(cgv::math::translate4(_position));
    ctx.mul_modelview_matrix(cgv::math::scale4(_size));
 
    if(_orientation == GizmoOrientation::kLocal)
        ctx.mul_modelview_matrix(_rotation.get_homogeneous_matrix());
    
    ctx.push_depth_test_state();
    ctx.disable_depth_test();
 
    ctx.push_blend_state();
    ctx.enable_blending();
    ctx.set_blend_func_back_to_front();
 
    draw_geometry(ctx);
 
    ctx.pop_blend_state();
 
    ctx.pop_depth_test_state();
 
    ctx.pop_modelview_matrix();
}
 
bool gizmo::handle(cgv::gui::event& e) {
    if(!cgv::render::drawable::get_active() || e.get_kind() != cgv::gui::EID_MOUSE)
        return false;
 
    cgv::gui::mouse_event& me = dynamic_cast<cgv::gui::mouse_event&>(e);
 
    context* ctx = get_context();
    if(!_view || !ctx)
        return false;
 
    const ivec4& viewport = ctx->get_window_transformation_array().front().viewport;
    vec2 viewport_size = vec2(viewport.z(), viewport.w());
 
    // get the mouse position in GL space
    ivec2 mouse_pos(
        static_cast<int>(me.get_x()),
        viewport_size.y() - static_cast<int>(me.get_y()) - 1
    );
 
    cgv::math::ray3 ray(vec2(mouse_pos), viewport_size, _view->get_eye(), ctx->get_projection_matrix() * ctx->get_modelview_matrix());
 
    bool evaluate_hover_state = false;
 
    switch(me.get_action()) {
    case cgv::gui::MA_MOVE:
        evaluate_hover_state = !_captured_mouse;
        break;
    case cgv::gui::MA_PRESS:
        if(_hovered && _interaction_feature != InteractionFeature::kNone) {
            if(start_drag(ray)) {
                _drag_start_ray = ray;
                _captured_mouse = true;
                return true;
            }
        }
        break;
    case cgv::gui::MA_RELEASE:
        if(_captured_mouse) {
            end_drag(ray);
            _captured_mouse = false;
            evaluate_hover_state = true;
        }
        break;
    case cgv::gui::MA_DRAG:
        if(_captured_mouse && drag(ray))
            return true;
        break;
    default:
        break;
    }
 
    if(evaluate_hover_state) {
        // transform ray to gizmo object space
        cgv::math::ray3 ray_object = ray;
        ray_object.origin -= _position;
        ray_object.origin /= _size;
 
        if(_orientation == GizmoOrientation::kLocal) {
            _rotation.inverse_rotate(ray_object.origin);
            _rotation.inverse_rotate(ray_object.direction);
        }
 
        bool was_hovered = _hovered;
        InteractionFeature last_feature = _interaction_feature;
        AxisId last_axis_id = _interaction_axis_id;
 
        _hovered = intersect_bounding_box(ray_object) && intersect(ray_object);
 
        if(was_hovered != _hovered || last_feature != _interaction_feature || last_axis_id != _interaction_axis_id) {
            set_geometry_out_of_date();
            post_redraw();
        }
    }
 
    return false;
}
 
GizmoOrientation gizmo::get_orientation() const {
    return _orientation;
}
 
void gizmo::set_orientation(GizmoOrientation orientation) {
    _orientation = orientation;
    post_redraw();
}
 
vec3 gizmo::get_position() const {
    return _position;
}
 
void gizmo::set_position(const vec3& position) {
    _position = position;
    post_redraw();
}
 
quat gizmo::get_rotation() const {
    return _rotation;
}
 
void gizmo::set_rotation(const quat& rotation) {
    _rotation = rotation;
    post_redraw();
}
 
float gizmo::get_size() const {
    return _size;
}
 
const cgv::render::view* gizmo::get_view() const {
    return _view;
}
 
void gizmo::set_geometry_out_of_date() {
    _geometry_out_of_date = true;
}
 
bool gizmo::captured_mouse() const {
    return _captured_mouse;
}
 
bool gizmo::is_hovered() const {
    return _hovered;
}
 
vec3 gizmo::get_axis(int index) const {
    assert(index >= 0 && index < 3);
    vec3 axis(0.0f);
    axis[index] = 1.0f;
    return axis;
}
 
vec3 gizmo::get_axis_mask(InteractionFeature feature, AxisId axis_id) const {
    switch(feature) {
    case InteractionFeature::kAxis:
        return get_axis(axis_id_to_index(axis_id));
    case InteractionFeature::kPlane:
        return vec3(1.0f) - get_axis(axis_id_to_index(axis_id));
    case InteractionFeature::kCenter:
        return vec3(1.0f);
    default:
        return vec3(0.0f);
    }
}
 
int gizmo::axis_id_to_index(AxisId axis) const {
    return static_cast<int>(axis);
}
 
gizmo::AxisId gizmo::index_to_axis_id(int idx) const {
    assert(idx >= 0 && idx < 3);
    return static_cast<AxisId>(idx);
}
 
}
}