Class: RedBird::Text

Inherits:
Data
  • Object
show all
Defined in:
ext/red_bird/text.c,
ext/red_bird/text.c

Overview

A text to be printed on the screen. This class renders the text received during the initialization as an image and store the image internally for rendering.

Author:

  • Frederico Linhares

Instance Method Summary collapse

Constructor Details

#initialize(text, font, tx_color, bg_color) ⇒ Object

Parameters:

  • text (String) —

    text to rendered.

  • font (RedBird::Font) —

    font to be used for rendering the text.

  • tx_color (RedBird::Color) —

    text color.

  • bg_color (RedBird::Color, nil) —

    if the attribute is a color, this color will be used as background; if the attribute is nil, there will be no background.

Author:

  • Frederico Linhares



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# File 'ext/red_bird/text.c', line 68

VALUE
bird_cText_initialize(VALUE self, VALUE text, VALUE font, VALUE tx_color,
                      VALUE bg_color)
{
  SDL_Surface *surface = NULL;

  struct bird_text_data *ptr;
  struct bird_font_data *font_ptr;
  struct bird_color_data *tx_color_ptr;
  struct bird_color_data *bg_color_ptr;

  if(!engine_initialized)
    rb_raise(rb_eRuntimeError, "%s",
             "can not create a RedBird::Text instance before RedBird::Engine "
             "is started");

  SafeStringValue(text);

  if(!rb_obj_is_kind_of(font, bird_cFont))
  {
    rb_raise(rb_eTypeError, "%s", "font must be an instance of RedBird::Font");
    return self;
  }

  if(!rb_obj_is_kind_of(tx_color, bird_cColor))
  {
    rb_raise(rb_eTypeError, "%s",
             "tx_color must be an instance of RedBird::Color");
    return self;
  }

  font_ptr = bird_cFont_get_data(font);
  tx_color_ptr = bird_cColor_get_data(tx_color);
  if(TYPE(bg_color) == T_NIL)
  {
    surface = TTF_RenderUTF8_Solid(font_ptr->data, StringValueCStr(text),
                                   tx_color_ptr->data);
  }
  else if(rb_obj_is_kind_of(bg_color, bird_cColor))
  {
    bg_color_ptr = bird_cColor_get_data(bg_color);
    surface = TTF_RenderUTF8_Shaded(font_ptr->data, StringValueCStr(text),
                                    tx_color_ptr->data, bg_color_ptr->data);
  }
  else
  {
    rb_raise(rb_eTypeError, "%s",
             "bg_color must be an instance of RedBird::Color or nil");
    return self;
  }

  if(surface == NULL)
  {
    rb_raise(rb_eRuntimeError, "failed to render text: %s", TTF_GetError());
    return self;
  }

  TypedData_Get_Struct(self, struct bird_text_data, &bird_text_type, ptr);

  ptr->data = NULL;
  ptr->data = SDL_CreateTextureFromSurface(bird_core.renderer, surface);
  SDL_FreeSurface(surface);
  if(ptr->data == NULL)
  {
    rb_raise(rb_eRuntimeError, "failed to convert text: %s", SDL_GetError());
    return self;
  }

  SDL_QueryTexture(ptr->data, NULL, NULL, &ptr->width, &ptr->height);
  return self;
}

Instance Method Details

#height ⇒ Integer

Returns the height of the image.

Returns:

  • (Integer) —

    text height.

Author:

  • Frederico Linhares



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# File 'ext/red_bird/text.c', line 162

VALUE
bird_cText_height(VALUE self)
{
  struct bird_text_data *ptr;

  TypedData_Get_Struct(self, struct bird_text_data, &bird_text_type, ptr);

  return INT2FIX(ptr->height);
}

#render_to_screen(x, y) ⇒ RedBird::Sprite

Render this text to the screen.

Parameters:

  • x (Integer) —

    screen horizontal position.

  • y (Integer) —

    screen vertical position.

Returns:

Author:

  • Frederico Linhares



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# File 'ext/red_bird/text.c', line 180

VALUE
bird_cText_render_to_screen(VALUE self, VALUE  x, VALUE  y)
{
  SDL_Rect dst_rect;

  struct bird_text_data *ptr;

  RB_INTEGER_TYPE_P(x);
  RB_INTEGER_TYPE_P(y);

  TypedData_Get_Struct(self, struct bird_text_data, &bird_text_type, ptr);

  dst_rect.x = NUM2INT(x);
  dst_rect.y = NUM2INT(y);
  dst_rect.w = ptr->width;
  dst_rect.h = ptr->height;

  SDL_RenderCopy(bird_core.renderer, ptr->data, NULL, &dst_rect);

  return self;
}

#width ⇒ Integer

Returns the width of the image.

Returns:

  • (Integer) —

    text width.

Author:

  • Frederico Linhares



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# File 'ext/red_bird/text.c', line 146

VALUE
bird_cText_width(VALUE self)
{
  struct bird_text_data *ptr;

  TypedData_Get_Struct(self, struct bird_text_data, &bird_text_type, ptr);

  return INT2FIX(ptr->width);
}