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File formats: DrawFile (changes)

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Programmer's Reference Manuals

» File Formats

» DrawFile

A DrawFile consists of a File Header block, followed by zero or more Object blocks.

Offset	Length	Contents
0	4	“Draw”
4	4	Major version, 201 at present
8	4	Minor version
12	12	Name of producing program, padded with spaces
24	4	X low bounding box
28	4	Y low bounding box
32	4	X high bounding box
36	4	Y high bounding box

Object Block

Offset	Length	Contents
0	4	Object Type Identifier:
		0 Font table
		1 Text object
		2 Path object
		3 (unimplemented Rectangle object)
		4 (unimplemented Rectangle object)
		5 Sprite object
		6 Group object
		7 Tagged object
		8 Not used
		9 Text area object
		10 Text column object
		11 Options object
		12 Transformed text object
		13 Transformed sprite object
		14 Not used
		15 Not used
		16 JPEG object
		17 Grid options object
4	4	Word aligned size, including header
8	16	Bounding box (not all types have this)
n	n	Object specific data, if any

Controlling sources: Hdr:DrawObj managed by the allocations manager

Font Table Object (Object Type 0)

This object has no bounding box. It should only appear once, and before any text objects.

It consists of:

a series of data items, where each data item consists of
- a font number (byte), followed immediately by
- a null terminated fontname
Then the table itself is padded to the word boundary with nulls.

Text Object (Object Type 1)

Offset	Length	Contents
24	4	Text colour
28	4	Background hint
32	4	Text style
36	4	X-size (in 1/640’s of a point)
40	4	Y-size (ie draw units)
44	4	X coord of start of baseline
48	4	Y coord of it
52	4	Zero terminated string padding

Path Object (Object Type 2)

Offset	Length	Contents
24	4	Fill colour (-1 for none)
28	4	Outline col (-1 for none)
32	4	Outline width
36	4	Path style
40	n	Optional dash pattern
40	n	Path components (consists of a Tag Identifier)

Tag Identifier

Offset	Length	Value	Meaning
+0	4		Tag ID:
		0	End of Path
		2	Move, one point
		5	Close sub-path
		6	Bezier, three points
		8	Line, one point
+4	n	0 – 3	sets of (x,y) dependant on tag

Sprite Object (Object Type 5)

This is followed by a sprite, which is scaled to fill bounding box.

Group Object (Object Type 6)

Offset	Length	Contents
0	12	Group object name (padded with spaces)

and then a sequence of objects. These will all lie within the bounding box of this.

Tagged Object (Object Type 7)

Offset	Length	Contents
0	4	Tagged identifier

and then followed by an object and optional word-aligned data.

Text Area Object (Object Type 9)

First, 1 or more text columns and then:

Offset	Length	Contents
0	4	Zero to mark end of columns
4	4	Reserved
8	4	Reserved
12	4	Initial foreground colour
16	4	Initial background hint
20	n	Zero terminated body of text
padding

Text Column Object (Object Type 10)

No data other than the standard 6 word header – the bounding box in the header gives the location of the column. Text column objects can only occur in Text area objects.

Options Object (Object Type 11)

This object has space for a bounding box, but the 4 words should be set to zero.

Offset	Length	Contents
0	4	Paper size
4	4	Paper limits
8	8	Grid spacing (floating point)
16	4	Grid division
20	4	Grid type
24	4	Grid auto-adjust
28	4	Grid visible
32	4	Grid units
36	4	Zoom multiplier (1 – 8)
40	4	Zoom divider (1 – 8)
44	4	Zoom locking
48	4	Toolbox Presence
52	4	Initial entry mode
56	4	Undo buffer (size in bytes)

Paper Size

Value	Meaning
&100	A0
&200	A1
&300	A2
&400	A3
&500	A4
&600	A5
&700	A6
&800	A7

Paper Limits

Bit	Meaning when set
0	Show limits
1 – 3	Reserved
4	Landscape (otherwise Portrait)
5 – 7	Reserved
8	Default to printer limits
9 – 31	Reserved

Grid Type

Value	Meaning
0	Rectangular grid
<> 0	Isometric grid

Grid Auto-adjust

Value	Meaning
0	Auto-adjust is disabled
<> 0	Auto-adjust is enabled

Grid Visible

Value	Meaning
0	Grid is not visible
<> 0	Grid is visible

Grid Units

Value	Meaning
0	Grid units is inches
<> 0	Grid units is cm

Zoom Locking

Value	Meaning
0	Zoom locking is set to none
<> 0	Zoom locking is set to powers of 2

Toolbox Presence

Value	Meaning
0	Toolbox is absent
<> 0	Toolbox is present

Initial Entry Mode

Bit	Meaning when set
0	Line
1	Closed line
2	Curve
3	Closed curve
4	Rectangle
5	Ellipse
6	Text line
7	Select

Transformed Text Object (Object Type 12)

Offset	Length	Contents
24	24	Transformation matrix
48	4	Font flags
52	4	Text colour
56	4	Background hint
60	4	Text style
64	4	X-size (in 1/640’s of a point)
68	4	Y-size (ie draw units)
72	4	X coord of start of baseline
76	4	Y coord of it
80	4	Zero terminated string padding
padding

Font Flags

Bit	Meaning when set
0	Kern text
1	Right to left

Transformed Sprite Object (Object Type 13)

Offset	Length	Contents
24	24	Transformation matrix
48	-	Format of sprite

This is scaled to fill the bounding box.

JPEG Object (Object Type 16)

Offset	Length	Contents
24	4	Height (draw units)
28	4	Width
32	4	x DPI (90 for a normal square pixel mode)
36	4	Y DPI
40	24	Transformation matrix
64	4	Length of JPEG data
68	n	Embedded JPEG (strictly JFIF) file
..	0 – 3	Padding to next word

Currently it seems that the 6 word transformation matrix is used only to scale the JPEG image and translate it from (0,0),(height,width) to the required position on the page. It is not known whether this object can contain JPEG data in any format other than a JFIF file.

Text Style

First (lowest) byte is fontnumber, and refers to font in font table.
The rest of word is reserved, and should be zero.

Path Style

Bit	Value	Meaning
0 – 1		Join style:
	0	Mitred
	1	Round
	2	Bevelled
2 – 3		Start cap:
	0	Butt
	1	Round
	2	Square
	3	Triangle
4 – 5		End cap
6		Winding rule:
	0	Non-zero
	1	Even-odd
7		Dash pattern
	0	None
	1	Present
16 – 23		Triangle cap width
24 – 31		Triangle cap length

Escape Sequence in Draw Text Area

_<^ Sequence	Meaning
\!<version>/	Version must be 1
\A	Alignment: L, R, C, D
\B<R> <G> <B>/	Set background hint
\C<R> <G> <B>/	Set foreground colour
\D<number>/	Number of columns
\F<digit><name> <size> [<width>]/	Declare a font
\<digit>	Select a font
\L<value>/	Leading
\M<left> <right>/	Sets margins
\P<value>/	Paragraph leading
\U<pos> <thickness>/	Turn on underline
\V[-]<digit>	Vertical move
\-	Soft hyphen
\<newline>	Force line break
\\	“\”
\; <newline>	Comment

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