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Original Author Paul Laughton, 2011
Page 183
De Re BASIC!
TYPE
POSITION 1
(numeric)
POSITION 2
(numeric)
ANGLE/RADIUS
(numeric)
UNIQUE
(various)
PAINT
(list ptr)
ALPHA
(num)
SH
APES

an
d

OBJ
EC
TS
arc
left
top
right bottom
start_angle
sweep_angle
fill_mode
paint
alpha
bitmap
x
y
bitmap
paint
alpha
circle
x
y
radius
paint
alpha
line
x1
y1
x2
y2
paint
alpha
oval
left
top
right bottom
paint
alpha
pixels
x
y
paint
alpha
point
x
y
paint
alpha
poly
x
y
list
paint
alpha
rect
left
top
right bottom
paint
alpha
text
x
y
text
paint
alpha
MODI-
FIERS
clip
left
top
right bottom
RO
paint
alpha
group
list
paint
alpha
rotate
x
y
angle
paint
alpha
TABLE NOTES:
The TYPE column shows the string returned by Gr.get.type for each graphical object type.
Gr.get.position returns the values in the POSITION 1 columns.
All table entries are Gr.modify tags (strings). Values of all the tags are numeric except for "text".
The values of tags in the UNIQUE column are either strings ("text") or numbers with special
interpretations. "fill_mode" is a logical value. "list" is a pointer to a list of point coordinates. "RO" is
a Region Operator as explained in Gr.clip.
"alpha" is an integer value from 0 to 256, with 256 interpreted specially. See General Purpose
Parameters
, below.
You can modify the Gr.set.pixels point-coordinates array directly. There is no Gr.modify tag.
For example, suppose a bitmap object was created with
Gr.bitmap.draw BM_ptr, galaxy_ptr, 400, 120
.
Executing
gr.modify BM_ptr, "x", 420
would move the bitmap from x =400 to x = 420.
Executing
gr.modify BM_ptr, "y", 200
would move the bitmap from y = 120 to y = 200.
Executing
gr.modify BM_ptr, "x", 420, "y", 200
would change both x and y at the same time.
Executing
gr.modify BM_ptr, "bitmap", Saturn_ptr
would change the bitmap of an image of a
(preloaded) Galaxy to the image of a (preloaded) Saturn.
General Purpose Parameters
When you create a graphical object, all the graphics settings (color, stroke, text settings, and so forth)
are captured in a Paint object. You can use the "paint" parameter to replace the Paint object, changing
any graphics setting you want to. See the Gr.paint.get command description (below) for more details.
Normally, graphical objects get their alpha channel value (transparency) from the latest Gr.color
command. You can change the "alpha" parameter to any value from 0 to 255. Setting alpha to 256 tells
BASIC! to use the alpha from the latest color value.