[.. upper level ..]

Miscellaneous functions

Functions for other useful staff.

• Structures and Enumerations


• Error functions
  Set and get error messages.
• VG3_seterror()
  
  Set an errno-value and an error text.
• VG3_error()
  
  Return last error text.
• VG3_errmsg()
  
  Return last errno-value and error text.


• Various functions
  
• VG3_version()
  
  Return version of VgaGames3.
• VG3_wait_time()
  
  Called once a game-loop, wait until the loop consumed a defined time.
• VG3_pause()
  
  Pause the game (if no network-game).
• VG3_get_xy_direction_from_angle()
  
  Return x-/y-directions of a given angle.
• VG3_get_angle_from_xy_direction()
  
  Return the angle of given x-/y-directions.
• VG3_uint_of_buffer()
  
  Calculate a number of an arbitrary byte-buffer using the Horner's scheme.
• VG3_time_delta()
  
  Return the time-difference in milliseconds since last call.


• Color- and brightness functions
  
• VG3_color_brightness()
  
  Return a color of reduced or enlightened brightness.
• VG3_colordef_colorize_to()
  
  Return a window-attributes setting value for colorizing the window.
• VG3_colordef_colorize_from()
  
  Return colorname, colordepth and brightness-overdriving from a window-attributes setting value for colorizing the window.


• Complexer handling with text and input
  
• VG3_utf8_to_iso()
  
  Convert a UTF-8 text into a ISO-8859-1 text (to use fontfiles).
• VG3_draw_textline()
  
  Draw a line of text at current position and update position for drawing next line.
• VG3_input_box()
  
  Show an input-box for entering a textline.
• VG3_input_select()
  
  Show a menu-box for selecting an element.
• VG3_input_image_select()
  
  Show a set of images for selecting an element.
• VG3_output_text()
  
  Show a box containing text.
• VG3_text_simpledraw()
  
  Draw simplified a text onto an image or the window.
• VG3_text_with_images()
  
  Create an image containing text and images.


• Simplifying key-handling with System-menu (and networking)
  
• VG3_keys_new()
  
  Return an initialized empty keys-struct.
• VG3_keys_free()
  
  Destroy the keys-struct.
• VG3_keys_menu_insert()
  
  Insert an entry into keyboard-menu and gamecontroller-/joystick-menu
  of the system-menu for all found devices and respect individual saved values.
• VG3_keys_nw_addkeys()
  
  Add all keys from the system-menu for a given device into the network structure,
  defining them as network-keys.
• VG3_keys_key_ispressed()
  
  Check if a specific key from the system-menu is pressed,
  and for a specific client if using network.


• Calculating image positions
  
• VG3_correct_imageposition()
  
  Adjust rectangle of a resized image for being drawn onto the same position.
• VG3_line_positions()
  
  Set an array with positions on a line between a start- and end-position.
• VG3_init_windowpos_on_bgimage()
  
  Drawing a section of the background-image which is larger than the window:
  Initialize the positioning structure.
• VG3_get_windowpos_on_bgimage()
  
  Drawing a section of the background-image which is larger than the window:
  Return delta x-/y-coordinates which have to be added when drawing the background-image.


• Object moving and collision detecting function
  
• VG3_move_object_check_collision()
  
  Function to simplify moving an instance of a VgaGames3-object and checking for collisions.