Gadget 0.1

To create an artwork, one types a set of commoands into a text file and then passes that file to the Gadget system, which will read the file and follow the instructions. Fisrt, double click on the Gadget program, names Gadget2024.exe, to start executing it. The Gadget program will ask for the text file containing the commands:

Double click on the text file you wish to execute. As an example, let's click on the file "03threshold.txt". The file will be opened and the text will be shown on the left side of the window, and the drawing area or canvas where the result will be displayed is on the right side of the window:

The image shown on the right is the result of the script that appears on the left. In this case the script has 5 lines:

# Threshold 
input x = hulio.jpg          # read the image
copy a x                     # Make a copy of x in a
togrey x                     # Convert x to grey levels only
threshold x 128              # Levels below 128 are black
display x

The second line is
input x = hulio.jpg # read the image
and looks for an image file named "hulio.jpg" and reads it into a variable named x. Any time the name x is referred to in this scripy it will reference this specific image.
The third line is
copy a x # Make a copy of x in a
This makes a copy of the image we just read into x, and assigns it to the variable a. Now we have two copies.

The next command is
togrey x # Convert x to grey levels only
which converts the color image in x in one that has only grey values. We don't see any result because we don't ask for x to be displayed.

The next command is
threshold x 128 # Levels below 128 are black
which changes all pixels in the image x to be black if the value is less than 128, and to white otherwise. Grey pixels can have values between 0 and 255, where 0 is black and 255 is white.

The final command is
display x
which displays the image x in the canvas region.

The process of creating a genberative work is to make a text file of the commands needed to draw the desired work, save it, and then run Gadget, loading this file at the inital step. Obviously you will wish to save the image, and learn more about what Gadget can do. Let's look at each of the possible commands, in alphabetical order.

Gadget Commands

all x

all
  get x
  print  red(x)
end

assign x y

background r g b a

block

camera a

close a

close a n

colorize x

contrast a min max

copy x y

dilate a

dilate a n

display x

edgesobel x

edgelaplace x

ellipse x i j w h

end

equalize a

erode a

erode a n

exit n

fillcolor r g b

get x

get c y i j

get x y i j w h

huesample x n

imageadd a b

imagesubtract a b

input x = filename

input x

line x a b c d

linecolor r g b

lineweight n

loop

loop n

mean m x

meanfilter n

medianfilter n

measure x y NAME

negative x

new x w h

noise a pa p2

open a

Morphological OPEN on image a by 1 layers.

print x

rect x a b w h

region x y i j w h

regionfill x i j r g b

replace y x i j

resize x n m

rotate x a

save x name

set c

set x i j c

speed n

threshold x t

triangle z x1 y1 x2 y2 x3 y3

tocolor c r g b

togrey x

valuesample x

variable x y

when a op b

Gadget expressions

Functions:

Examples

Example 1 - Display

input x = image.jpg
display x

Example 2 - Convert to grey levels

# Sample Gadget program - Anything after '#' is ignored
input x = hulio.jpg          # read the image
copy a x                            # Make a copy of x in a
togrey x                            # Convert x to grey levels only
display x                           # Display it.

Example 3 - Threshold using the mean value

# Mean threshold
input x = hulio.jpg          # read the image
copy a x                     # Make a copy of x in a
togrey x                     # Convert x to grey levels only
mean a x                     # What is the mean grey level in x?
threshold x [a]              # Levels below a are black
display x

Example 4 - Draw an ellipse

# Sample graphics
new x 400 400
lineweight 10
fillcolor 255 0 0
linecolor 0 0 255
ellipse x 100 100 90 78
display x

Example 5 - Fill

# fill a region
input x = small.png
regionfill x 100 100 [random(150)+50] [random(200)] [random(100)+100]
display x

Example 6 - Set all pixels

# Set all pixels to 200 200 90
new x 200 200
all x
    tocolor c 200 200 90
    set c
end
display x

Example 7 - Set all pixels again

# Set all pixels to 200 200 90
new x 200 200
tocolor c 200 200 90
all x
    set c
end
display x

Example 8 - when

input x = small.png
all x
  get c
  when [red(c)] == [0]
    regionfill x ROW COLUMN 255 0 0
  end
end
display x

Example 9 - Artwork, watercolor

# Replace pixels with strokes
input im = wc2.jpg
loop 5000                          # 5000 pixels
 assign x [random(width(im))]      # random pixel location, x
 assign y [random(height(im))]     # random pixel location, y
 assign w [random(4)+2]            # Random width between 4 and 6
 lineweight w
 assign d [random(15)-8]           # Position variation between -7 and +7
 assign x0 [x-d]                   # Line start is (x0,y0)
 assign x1 [x+d]
 assign d [random(15)-8]           # Position variation between -7 and +7
 assign y0 [y-d]                   # Line end is (x1,y1)
 assign y1 [y+d]
 get p im x y                      # Get the color at location (x,y)
 linecolor [red(p)] [green(p)] [blue(p)]
 line im x0 y0 x1 y1               # Draw a line
end
display im

Example 9 - Artwork, shading

input x = hulio.jpg
new v [width(x)] [height(x)]
togrey x
all x
  region z x COLUMN ROW 10 10
  mean m z
  when [random(5.5)] > [m/25]
    assign i COLUMN
    assign j ROW
    line v [i+2] [j+2] [i-2] [j-2]
  end
end
display v

Example 10 - Artwork, patches

new im 1000 800               # The empty canvas
background im 0 0 0           # Black background
assign dw 100                 # Base width or rectangle
assign dh 90                  # Base height
assign R  [random(155)+100]   # Random (r,g,b) between (155,155,155)
assign G  [random(155)+100]   #  and (255,255,255)
assign B  [random(155)+100]
assign n 222                  # Create 222 rectangles
loop n
  assign x [random(980)+20]   # Random position in the image.
  assign y [random(780)+20]
  assign wid [random(dw-10)+dw] # Random width based on dw
  assign ht [random(dh-10)+dh]  # Random height based on dh
  assign r [random(R-40)+20]    # Random variation on the (R,G,B) given
  assign g [random(G-40)+20]
  assign b [random(B-40)+20]
  when [R+20] > 255             # If any color component exceeds 255, modify it
    assign r [random(255-(R-20))+(R-20)]
  end
  when [R+20] > 255
    assign r [random(255-(R-20))+(R-20)]
  end
  when [G+20] > 255
    assign g [random(255-(G-20))+(G-20)]
  end
  when [B+20] > 255
    assign b [random(255-(B-20))+(B-20)]]
  end
  fillcolor r g b 30          # Fill with the selected RGB color
  rect im x y wid ht          # Draw the rectangle
end
display im
save im out.png

Example 11 - Color changer

input x = imageb.jpg
display x
all x                                    #For every pixel
  when PIXEL.GREEN >= PIXEL.RED          # if green is the largest color component
    when PIXEL.GREEN >= PIXEL.BLUE
      tocolor c 0 255 0
      set c                              # set this pixel to full green
    end
  end
  when PIXEL.RED >= PIXEL.GREEN          # if red is the largest color component
    when PIXEL.RED >= PIXEL.BLUE
      tocolor c 255 0 0
      set c                              # set this pixel to full red
    end
  end
  when PIXEL.BLUE >= PIXEL.RED
    when PIXEL.BLUE >= PIXEL.GREEN
      tocolor c 0 0 255
      set c
    end
  end
end
display x