libcaca documentation

Functions
libcaca primitives drawing

## Functions
__extern int | caca_draw_line (caca_canvas_t *, int, int, int, int, uint32_t)
| Draw a line on the canvas using the given character.
__extern int | caca_draw_polyline (caca_canvas_t *, int const x[], int const y[], int, uint32_t)
| Draw a polyline.
__extern int | caca_draw_thin_line (caca_canvas_t *, int, int, int, int)
| Draw a thin line on the canvas, using ASCII art.
__extern int | caca_draw_thin_polyline (caca_canvas_t *, int const x[], int const y[], int)
| Draw an ASCII art thin polyline.
__extern int | caca_draw_circle (caca_canvas_t *, int, int, int, uint32_t)
| Draw a circle on the canvas using the given character.
__extern int | caca_draw_ellipse (caca_canvas_t *, int, int, int, int, uint32_t)
| Draw an ellipse on the canvas using the given character.
__extern int | caca_draw_thin_ellipse (caca_canvas_t *, int, int, int, int)
| Draw a thin ellipse on the canvas.
__extern int | caca_fill_ellipse (caca_canvas_t *, int, int, int, int, uint32_t)
| Fill an ellipse on the canvas using the given character.
__extern int | caca_draw_box (caca_canvas_t *, int, int, int, int, uint32_t)
| Draw a box on the canvas using the given character.
__extern int | caca_draw_thin_box (caca_canvas_t *, int, int, int, int)
| Draw a thin box on the canvas.
__extern int | caca_draw_cp437_box (caca_canvas_t *, int, int, int, int)
| Draw a box on the canvas using CP437 characters.
__extern int | caca_fill_box (caca_canvas_t *, int, int, int, int, uint32_t)
| Fill a box on the canvas using the given character.
__extern int | caca_draw_triangle (caca_canvas_t *, int, int, int, int, int, int, uint32_t)
| Draw a triangle on the canvas using the given character.
__extern int | caca_draw_thin_triangle (caca_canvas_t *, int, int, int, int, int, int)
| Draw a thin triangle on the canvas.
__extern int | caca_fill_triangle (caca_canvas_t *, int, int, int, int, int, int, uint32_t)
| Fill a triangle on the canvas using the given character.
__extern int | caca_fill_triangle_textured (caca_canvas_t *cv, int coords[6], caca_canvas_t *tex, float uv[6])
| Fill a triangle on the canvas using an arbitrary-sized texture.

## Detailed Description

These functions provide routines for primitive drawing, such as lines, boxes, triangles and ellipses.

## Function Documentation

__extern int caca_draw_line | ( | caca_canvas_t * | cv,
|  | int | x1,
|  | int | y1,
|  | int | x2,
|  | int | y2,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x1 | X coordinate of the first point.
  y1 | Y coordinate of the first point.
  x2 | X coordinate of the second point.
  y2 | Y coordinate of the second point.
  ch | UTF-32 character to be used to draw the line.

Returns:
  This function always returns 0.

Referenced by caca_draw_box(), caca_draw_triangle(), and caca_fill_ellipse().

__extern int caca_draw_polyline | ( | caca_canvas_t * | cv,
|  | int const | x[],
|  | int const | y[],
|  | int | n,
|  | uint32_t | ch
| ) |  |

Draw a polyline on the canvas using the given character and coordinate arrays. The first and last points are not connected, hence in order to draw a polygon you need to specify the starting point at the end of the list as well.

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | Array of X coordinates. Must have `n` + 1 elements.
  y | Array of Y coordinates. Must have `n` + 1 elements.
  n | Number of lines to draw.
  ch | UTF-32 character to be used to draw the lines.

Returns:
  This function always returns 0.

__extern int caca_draw_thin_line | ( | caca_canvas_t * | cv,
|  | int | x1,
|  | int | y1,
|  | int | x2,
|  | int | y2
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x1 | X coordinate of the first point.
  y1 | Y coordinate of the first point.
  x2 | X coordinate of the second point.
  y2 | Y coordinate of the second point.

Returns:
  This function always returns 0.

Referenced by caca_draw_thin_triangle().

__extern int caca_draw_thin_polyline | ( | caca_canvas_t * | cv,
|  | int const | x[],
|  | int const | y[],
|  | int | n
| ) |  |

Draw a thin polyline on the canvas using the given coordinate arrays and with ASCII art. The first and last points are not connected, so in order to draw a polygon you need to specify the starting point at the end of the list as well.

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | Array of X coordinates. Must have `n` + 1 elements.
  y | Array of Y coordinates. Must have `n` + 1 elements.
  n | Number of lines to draw.

Returns:
  This function always returns 0.

__extern int caca_draw_circle | ( | caca_canvas_t * | cv,
|  | int | x,
|  | int | y,
|  | int | r,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | Center X coordinate.
  y | Center Y coordinate.
  r | Circle radius.
  ch | UTF-32 character to be used to draw the circle outline.

Returns:
  This function always returns 0.

__extern int caca_draw_ellipse | ( | caca_canvas_t * | cv,
|  | int | xo,
|  | int | yo,
|  | int | a,
|  | int | b,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  xo | Center X coordinate.
  yo | Center Y coordinate.
  a | Ellipse X radius.
  b | Ellipse Y radius.
  ch | UTF-32 character to be used to draw the ellipse outline.

Returns:
  This function always returns 0.

__extern int caca_draw_thin_ellipse | ( | caca_canvas_t * | cv,
|  | int | xo,
|  | int | yo,
|  | int | a,
|  | int | b
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  xo | Center X coordinate.
  yo | Center Y coordinate.
  a | Ellipse X radius.
  b | Ellipse Y radius.

Returns:
  This function always returns 0.

__extern int caca_fill_ellipse | ( | caca_canvas_t * | cv,
|  | int | xo,
|  | int | yo,
|  | int | a,
|  | int | b,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  xo | Center X coordinate.
  yo | Center Y coordinate.
  a | Ellipse X radius.
  b | Ellipse Y radius.
  ch | UTF-32 character to be used to fill the ellipse.

Returns:
  This function always returns 0.

References caca_draw_line().

__extern int caca_draw_box | ( | caca_canvas_t * | cv,
|  | int | x,
|  | int | y,
|  | int | w,
|  | int | h,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | X coordinate of the upper-left corner of the box.
  y | Y coordinate of the upper-left corner of the box.
  w | Width of the box.
  h | Height of the box.
  ch | UTF-32 character to be used to draw the box.

Returns:
  This function always returns 0.

References caca_draw_line().

__extern int caca_draw_thin_box | ( | caca_canvas_t * | cv,
|  | int | x,
|  | int | y,
|  | int | w,
|  | int | h
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | X coordinate of the upper-left corner of the box.
  y | Y coordinate of the upper-left corner of the box.
  w | Width of the box.
  h | Height of the box.

Returns:
  This function always returns 0.

__extern int caca_draw_cp437_box | ( | caca_canvas_t * | cv,
|  | int | x,
|  | int | y,
|  | int | w,
|  | int | h
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | X coordinate of the upper-left corner of the box.
  y | Y coordinate of the upper-left corner of the box.
  w | Width of the box.
  h | Height of the box.

Returns:
  This function always returns 0.

__extern int caca_fill_box | ( | caca_canvas_t * | cv,
|  | int | x,
|  | int | y,
|  | int | w,
|  | int | h,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x | X coordinate of the upper-left corner of the box.
  y | Y coordinate of the upper-left corner of the box.
  w | Width of the box.
  h | Height of the box.
  ch | UTF-32 character to be used to draw the box.

Returns:
  This function always returns 0.

References caca_add_dirty_rect(), and caca_put_char().

Referenced by caca_conio_clreol().

__extern int caca_draw_triangle | ( | caca_canvas_t * | cv,
|  | int | x1,
|  | int | y1,
|  | int | x2,
|  | int | y2,
|  | int | x3,
|  | int | y3,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x1 | X coordinate of the first point.
  y1 | Y coordinate of the first point.
  x2 | X coordinate of the second point.
  y2 | Y coordinate of the second point.
  x3 | X coordinate of the third point.
  y3 | Y coordinate of the third point.
  ch | UTF-32 character to be used to draw the triangle outline.

Returns:
  This function always returns 0.

References caca_draw_line().

__extern int caca_draw_thin_triangle | ( | caca_canvas_t * | cv,
|  | int | x1,
|  | int | y1,
|  | int | x2,
|  | int | y2,
|  | int | x3,
|  | int | y3
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x1 | X coordinate of the first point.
  y1 | Y coordinate of the first point.
  x2 | X coordinate of the second point.
  y2 | Y coordinate of the second point.
  x3 | X coordinate of the third point.
  y3 | Y coordinate of the third point.

Returns:
  This function always returns 0.

References caca_draw_thin_line().

__extern int caca_fill_triangle | ( | caca_canvas_t * | cv,
|  | int | x1,
|  | int | y1,
|  | int | x2,
|  | int | y2,
|  | int | x3,
|  | int | y3,
|  | uint32_t | ch
| ) |  |

This function never fails.

Parameters:

  cv | The handle to the libcaca canvas.
  x1 | X coordinate of the first point.
  y1 | Y coordinate of the first point.
  x2 | X coordinate of the second point.
  y2 | Y coordinate of the second point.
  x3 | X coordinate of the third point.
  y3 | Y coordinate of the third point.
  ch | UTF-32 character to be used to fill the triangle.

Returns:
  This function always returns 0.

References caca_fill_triangle(), and caca_put_char().

Referenced by caca_fill_triangle().

__extern int caca_fill_triangle_textured | ( | caca_canvas_t * | cv,
|  | int | coords[6],
|  | caca_canvas_t * | tex,
|  | float | uv[6]
| ) |  |

This function fails if one or both the canvas are missing

Parameters:

  cv | The handle to the libcaca canvas.
  coords | The coordinates of the triangle (3{x,y})
  tex | The handle of the canvas texture.
  uv | The coordinates of the texture (3{u,v})

Returns:
  This function return 0 if ok, -1 if canvas or texture are missing.