text_billboard.hpp

// Copyright [2015] Albert Huang

#ifndef SCENEVIEW_TEXT_BILLBOARD__
#define SCENEVIEW_TEXT_BILLBOARD__

#include <memory>
#include <string>

#include <QFont>

#include <sceneview/font_resource.hpp>
#include <sceneview/geometry_resource.hpp>
#include <sceneview/material_resource.hpp>
#include <sceneview/resource_manager.hpp>
#include <sceneview/scene.hpp>

namespace sv {

class TextBillboardDrawable;
class DrawNode;
class GroupNode;
class Viewport;

class TextBillboard {
  public:
    enum HAlignment {
      kLeft = 4,
      kHCenter = 5,
      kRight = 6,
    };

    enum VAlignment {
      kBottom,
      kVCenter,
      kTop,
    };

    enum YDirection {
      kNegative = -1,
      kPositive = 1
    };

    typedef std::shared_ptr<TextBillboard> Ptr;

    static Ptr Create(Viewport* viewport, GroupNode* parent);

    ~TextBillboard();

    void SetText(const QString& text);

    void SetFont(const QFont& font);

    void SetLineHeight(float height);

    void SetTextColor(const QColor& color);

    void SetBackgroundColor(const QColor& color);

    void SetAlignment(HAlignment horizontal, VAlignment vertical);

    void SetYDirection(YDirection direction);

    GroupNode* Node() { return node_; }

  private:
    TextBillboard(Viewport* viewport,
        GroupNode* parent);

    void Recompute();

    Viewport* viewport_;
    ResourceManager::Ptr resources_;
    Scene::Ptr scene_;

    GroupNode* parent_;
    GroupNode* node_;

    FontResource::Ptr font_resource_;
    MaterialResource::Ptr bg_material_;
    GeometryResource::Ptr rect_geom_;
    MaterialResource::Ptr text_material_;
    GeometryResource::Ptr text_geom_;
    DrawNode* draw_node_;

    VAlignment v_align_;
    HAlignment h_align_;
    float line_height_;
    YDirection y_dir_ = kNegative;

    float margin_top_;
    float margin_left_;
    float margin_bottom_;
    float margin_right_;

    QFont qfont_;
    std::string text_;

    TextBillboardDrawable* bg_drawable_;
    TextBillboardDrawable* text_drawable_;
    TextBillboardDrawable* depth_write_drawable_;
};

}  // namespace sv

#endif  // SCENEVIEW_TEXT_BILLBOARD__