From 4c3af133d2ea67ff6052bdbcf17802354e36394f Mon Sep 17 00:00:00 2001
From: James Devine <devine.jd@gmail.com>
Date: Tue, 27 Jan 2015 15:43:59 -0800
Subject: [PATCH]

---
 gcodemake.pde | 137 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 137 insertions(+)
 create mode 100644 gcodemake.pde

diff --git a/gcodemake.pde b/gcodemake.pde
new file mode 100644
index 0000000..2d8cdf9
--- /dev/null
+++ b/gcodemake.pde
@@ -0,0 +1,137 @@
+/**
+ * Convert a JPG image to gcode for Mr Beam 
+ * To use, put the .jpg you want to use in the /data folder of your sketch and adjust the canvas size(x,y) to suit the image,
+ * Use the feedrate, laserfloor and lasermax variables to determine how fast and how hard it burns.
+ 
+ This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ 
+ */
+ 
+// The next line is needed if running in JavaScript Mode with Processing.js
+/* @pjs preload="bender.jpg"; */ 
+
+PImage img;  // Declare variable "a" of type PImage
+  float xbed =  435;
+  float ybed = 300;
+  float feedrate = 800;
+  float laserfloor = 90; //highest typical value
+  float lasermax = 255; //laser scale factor
+  float scale = 20;
+  int plotthresh = 30;
+  color c;
+  int oldgrey = 0;  
+
+PrintWriter output;
+
+void setup() {
+  size(299, 616);
+  // The image file must be in the data folder of the current sketch 
+  // to load successfully
+  img = loadImage("input.jpg");  // Load the image into the program  
+  noLoop();
+  output = createWriter("output.gco"); //this is the name of the output file
+  
+}
+
+void draw() {
+  // Displays the image at its actual size at point (0,0)
+  image(img, 0, 0);
+ 
+ 
+ //set up the output file
+ output.println("$H");
+ output.println("G92X0Y0Z0");
+ output.println("G90");
+ output.println("M08");
+ output.println("G21");
+ output.print("F");
+ output.println(feedrate);
+ 
+ 
+ for (int x = 0; x < width; x = x+2) { //the X axis loop
+  for (int y = 0; y < height; y++){ //the forward half of the y axis loop
+  
+  //y axis forward calculations
+  float xpos = x;
+  xpos = xpos/scale;
+    float ypos = y;
+  ypos = ypos/scale;
+     color c = get(x,y);
+     float red = red(c);
+     float green = green(c);
+     float blue = blue(c);
+     int grey = (int)(red+green+blue)/3;
+     color Color =color(grey,grey,grey);
+     set(x,y,Color);
+     grey = int(laserfloor-((float(grey)/256)*lasermax)); //this is where the laser scaling is done
+     //when considering the scale values remember 0 is black on the screen and 255 is white, so we want the reverse.
+
+//if the value is worth plotting, plot it, threshold is set above. Might give odd behaviour at edge cases.
+if ((grey != oldgrey)&(grey>plotthresh)) {
+  output.print("G1 ");
+  output.print('X');
+  output.print(nf(xpos,3,4));
+  output.print(" ");
+  output.print('Y'); 
+  output.print(nf(ypos,3,4));
+  output.print(" ");
+  output.print("M03 S");
+  output.println(grey);
+}
+
+
+oldgrey=grey; //pass the last pixel value back, so that the laser just runs on through pixels of the same colour
+
+  }
+for (int y = height-1; y > 0; y--){ //loop for negative Y axis, to optimise the raster scan pattern.
+
+//calculations for y axis negative cycle
+  float xpos = x+1;
+  xpos = xpos/scale;
+  float ypos = y;
+  ypos = ypos/scale;
+  color c = get(x+1,y);
+  float red = red(c);
+  float green = green(c);
+  float blue = blue(c);
+  int grey = (int)(red+green+blue)/3;
+  color Color =color(grey,grey,grey);
+  set(x+1,y,Color);
+  grey = int(laserfloor-((float(grey)/256)*lasermax));
+
+  
+if ((grey != oldgrey)&(grey>plotthresh)) { //switch to decide if pixel is worth plotting
+
+  output.print("G1 ");
+  output.print('X');
+  output.print(nf(xpos,3,4));
+  output.print(" ");
+  output.print('Y');
+  output.print(nf(ypos,3,4));
+  output.print(" ");
+  output.print("M03 S");
+  output.println(grey);
+}
+oldgrey = grey; //pass back the last pixel intensity value
+  }
+  
+}
+
+//close out the .gcode file by turning off the laser and the fan.
+output.println("M05");
+output.println("M09");
+output.flush(); // Writes the remaining data to the file
+output.close();
+//exit(); 
+}
\ No newline at end of file