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======GTF0======

=====GRABIT=====
The first step towards completing the project is to get the skeleton code and Makefile
Lab46 has a command you can run called grabit, it can be used by typing the command, followed by the course designation, followed by the project
in this case it would be 
<code> grabit cprog gtf0 </code>
=====REPOSITORY STEPS=====
=====BUILD THE CODE=====

Edit the provided skeletal code from the grabit using a txt editor like nano. edit this code to fit the criteria for the project

  


=====RUN THE PROGRAM=====

To be able to run the gtf0.c file use the following command in the grabit file:
<code>make debug</code>
Issue the command ''ls -l'' and if there is a green "gft0" file, everything worked :) {for now}

If you execute this command it should produce a .png image
=====VIEW THE IMAGE=====

The image can either be viewed, if on a Pi, from the GUI file explorer

Or if in lab46:
1. Copy the file to ~/public_html/
   
<code>username@lab46:~/src/spring2024/gtf0$ cp ./gft0.png ~/public_html</code>
     
2. Change current directory to ~/public_html 
   
<code>cd ~/public_html</code>
     
3. Change permissions to be able to be read by all
   
<code>chmod +r gtf0.png</code>
     
4.view image from web browser
   
<code>https://lab46.g7n.org/~username/gtf0.png</code>
=====LIBGD FUNCTIONALITY=====

====MIXING A COLOR====
You can make custom colors in C with commands from the libgd library
so do this specify the integer variable that will have the color assigned to it
<code>int black = 0;</code>
then using the gdImageColorAllocate command, specify the intensity of each color, red green and blue, and reassign the output to the color
<code>                         image  red   green blue
black = gdColorAllocate (image, 0x00, 0x00, 0x00);</code>

''red  green  blue'' sections are in hexcode so the most intense value is ''0xFF'' and the least being ''0x00'' 

so if <color #ed1c24>red</color> and <color #00a2e8>blue</color> = ''0xFF'' 

and <color #22b14c>green</color> = ''0x00'' 

you will get <color #c8bfe7>purple</color> 


====DRAWING A LINE==== 

Syntax for drawing a graphics line

<code>gdImageFill (image, x1, y1, x2, y2, color);</code>                   
====DRAWING A RECTANGLE====

Syntax for drawing a graphics line

<code>gdImageRectangle (image, topleftX, topleftY, bottomrightX, bottomrightY, colorofRectlines)</code>
====FILLING AN ENCLOSED SPACE====

Basically the Fill bucket from any drawing software.
You specify where the coordinates of the fill is (another way of thinking is that the coordinates is specifying where the "click" of the paint bucket tool would be on the screen) and all space within enclosed lines around the coord's get flooded with the specified color

<code>gdImageFill (image, x1, y1, color);</code>
====DRAWING A FILLED RECTANGLE====

Syntax for drawing a graphics line

<code>gdImageFilledRectangle (image, topleftX, topleftY, bottomrightX, bottomrightY, color)</code>

This will draw a solid rectangle of color
====DRAWING A CIRCLE====

Syntax for a circle uses an arc command but the start angle is 0° and the end is 360° 
(also the diameters are equal)

Arc syntax:
<code>gdImageArc (image, centerX, centerY, diameterWidth, diameterHeight, start°, end°, colorofLine);</code>

Circle Ex:
<code>gdImageArc (image 150, 300, 100, 100, 0, 360, black);</code>
====DRAWING AN ELLIPSE====

Syntax for an Ellipse
<code>gdImageEllipse ( X1, Y2, width, height, colorofLine);</code>
(could also be used for a circle)

Syntax for an Filled Ellipse
<code>gdImageFilledEllipse ( X1, Y2, width, height, colorofFill);</code>
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