Processing Forum

What are the 5 things a new programmer should learn first?

[6 Replies]
- 09-Apr-2012 04:20 PM
- Forum: General Discussion
Hello to the Processing community!

I know this is long but please bare with me because I could really use the help, thanks :)

I'm not exactly new here but I thought I would introduce myself, my name is Joe and I have been programming on and off since high school. I stopped after high school and started up again a couple years later in college, when I discovered Processing, and have been actively developing in my academic life since. I do spend a lot of my free time programming. Mostly proof of concept stuff but I have done a couple larger projects outside of school (and several in).

I am working with a local high school's intro programming class for my senior capstone project, and as part of my work I need to help teach them about computer programming. I have been trying for days to think about the things i could teach them and I just can't decide what the most important things are to establish a strong base line that will evolve into quality coding skills and a better understanding of programming and the application lifecycle. So I decided I would poll this wonderful community to see what people think about the subject, and here is my question for all of you:

Knowing what you know about programming right now (not necessarily Processing specific, but the students have used Processing before), what are the 5 things you think you should have learned about programming when you first began?

Now these could be specific skills, thought processes, best practices, about fundamentals of computer programming, how to write sort functions for arrays, what the difference is between == and .equals() for Strings, OOP skills, class design, or some topic in programming (math, physics, 2D transformations, graphics, game concepts, whatever). Anything at all so long as it pertains to programming and you wished you knew then what you know now.

I will be checking back in to the forum frequently tonight, hopefully we can get a good discussion going on of what people think the fundamentals of computer programming should be. Thanks for reading, and I hope to hear from each one of you!

GSoC - Proposals

[1 Reply]
- 05-Apr-2012 11:44 AM
- Forum: Library and Tool Development
I thought that we were able to propose our own projects, and now after further reading I am getting the feeling that it has to be one of the projects listed on the ideas page. Is this the case or can we propose own own projects that will be considered?

EDIT: just found this post: HERE , where Dan Shiffman explains that they will read and consider other proposals.

GSoC - 2D Android Game Engine/Library

[6 Replies]
- 04-Apr-2012 12:30 PM
- Forum: Library and Tool Development
I just found out that Processing was participating in GSoC, and I'm super excited. I would like to create an engine/set of libraries to assist in the creation of 2D games for android coded in Processing. I would like to incorporate a sprite/sprite sheet system that can read from multiple sources (i.e. plist, xml...) that can be generated by sprite sheet packers. The system would have controls for creating and utilizing animations from sprite sheets. Also I would include a tile map reader to import and build levels created in a tile map editor. Also included would be a system to create menus or layers (HUD or something like that) in the game, along with some common UI elements, a system to manage game settings, a physics system and anything else i haven't already thought of. I have been looking for an good android 2d game engine and having the ability to create them in Processing, a language I am extremely comfortable working in, would be fantastic. Let me know what you think!

can't export a working sketch - applet or application

[1 Reply]
- 11-Mar-2012 05:08 PM
- Forum: Integration and Hardware
I have tried 1.5.1 and 2.0.4a, tried exporting as an application(mac os x) and when exported from 2.0.4a the icon launches but nothing ever shows on the screen, and when exported from 1.5.1 all i get is a white application window. When i export it as an applet in both versions the applet won't run because of a class not found error (the main sketch class in fact). which i assume is the reason that the applications aren't working

I haven't moved any files from the export locations and i tried exporting on 2 different machines. Is this a known issue, or am i the only one experiencing it? kind of at a loss, i need to export my sketch asap for school. any help would be greatly appreciated.

[SOLVED] Does Fisica have a known MAX FWorld size?

[0 Replies]
- 10-Mar-2012 08:10 AM
- Forum: Contributed Library Questions
My sketch keeps freezing every time the sprite character in the sketch moves past twice the sketchs width inside the FWorld. It happens when the character jumps high enough as well. leads me to believe that there might be a max FWorld size. can anyone confirm this?

[UPDATE]: so the sketch isn't freezing but the sprite is getting stuck like it is getting stuck in the edge mof the world but there is no world edge there. i'll keep investigating

[SOLUTION]: i was calling the default constructor for FWorld and then calling setEdges, looks like i needed to set the edge parameters in the FWorld instantiation. like so: FWorld world = new FWorld(x, y, w, h);

[SOLVED] Is there a reserved word in Processing for accessing the Sketch's root class?

[9 Replies]
- 29-Feb-2012 11:42 AM
- Forum: Core Library Questions
I am saving versions of my sketch as I go along, changing the sketch name when I have a new version i want to save. i.e. sketch_v1_0, sketch_v1_1, sketch_v1_2, etc... I declare static fields and objects in the root class of the sketch (where the setup and draw functions are) and need to access them in other classes and methods, but I would like to not have to traverse my code each time i save to change each occurrence of 'sketch_v1_0' with 'sketch_v1_1' So i was wondering if there was a key/reserved word in processing that would allow me to access the root class without using the actual name. i.e. 'SKETCH' or 'SKETCHNAME' or something else instead of 'sketch_v1_0'. I have tried passing the parent PApplet from the root class to the places i need it but i get an error saying that the variable cannot be resolved or is not a field. Thanks in advance

BeanShell Scripting and accessing classes from the PDE

[2 Replies]
- 21-Feb-2012 08:18 PM
- Forum: Contributed Library Questions
So i am trying to get scripting running in Processing using BeanShell as a Java library. I can currently run code from a file but when trying to access classes that are not in processing.core, java, or an imported library, i.e. an sketches inner class created in the PDE i get an error that says the interpreter from beanshell can't find the class in the namespace. for example: if i had an external script file that contained the code
1. MyClass mc = new MyClass();
and MyClass is a class defined in a tab in the sketch it would throw the error. I am assuming that this is due to the fact that beanshell looks for .java files in the namespace, or so i read on their site, and that the classes saved in Processing are .pde files. i also read that there were complications or something with inner classes, i can't find the post i read online about all this, but it's on the beanshell website.
my question is does anyone know of a method to make the sketches inner classes available to the beanshell interpreter.so that i can use the sketches inner classes in scripts?

BeanShell bsh Interpreter defaulting file browsing directory to /Applications/ not in the sketch's root/data directory

[2 Replies]
- 18-Feb-2012 04:46 PM
- Forum: Contributed Library Questions
I am using the beanshell interpreter to read a file with code in it to be executed. I assumed that the default directory for file browsing would be the same as it is for the rest of the sketch, however when i run my sketch i get a file not found exception when i use this file path:
1. ./code/default-methods/exit.java or
2. code/default-methods/exit.java
And i get this as my error telling me that it is actually looking in /Applications/code/default-methods/ for exit.java:
1. java.io.FileNotFoundException: /Applications/code/default-methods/exit.java (No such file or directory)
and if i use
1. /code/default-methods/exit.java
i then see this:
java.io.FileNotFoundException: /code/default-methods/exit.java (No such file or directory)
here is the code i am using:
1. import bsh.*;
2. private Interpreter decoder = new Interpreter();
3. //callMethod is called by a class function
4. private void callMethod(String method) {
5. println(method);
6. String file = "/code/default-methods/"+method+".java";
8. try {
9. decoder.source(file);
10. }
11. catch (FileNotFoundException fnfe) {
12. println("File Not Found:");
13. fnfe.printStackTrace();
14. }
15. catch(IOException ioe) {
16. println("IOException:");
17. ioe.printStackTrace();
18. }
19. catch(EvalError err) {
20. println("EvalError:");
21. err.printStackTrace();
22. }
23. }
does anyone know why the default directory for file browsing when calling source on the bsh interpreter object would be /Applications/code/ and not /data/code but when i use proxml to save xml files i use ./xml/accounts/accounts.xml to save a file where /code/ and /xml/ are in the same folder, that the default directory is the sketchs data folder?

any help would be greatly appreciated

problem passing parameter from controlP5 Textfield method

[1 Reply]
- 21-Jan-2012 12:22 PM
- Forum: Contributed Library Questions
I am trying to pass the value of a ControlP5 Textfield out of the user-named method to get the value to a class method but i am getting this error:
1. Jan 21, 2012 3:02:03 PM controlP5.ControlBroadcaster printMethodError
2. SEVERE: An error occured while forwarding a Controller value
3. to a method in your program. Please check your code for any
4. possible errors that might occur in this method .
5. e.g. check for casting errors, possible nullpointers, array overflows ... .
6. method: inputField
7. exception: java.lang.reflect.InvocationTargetException
and here is the code i am using:
1. ControlP5 gui;
2. gui = new ControlP5(this);
3. String consoleText;
4. Textfield inputField;
5. inputField = gui.addTextfield("inputField", 0, height-26, width-1, 25);
6. inputField.keepFocus(true);
8. public void inputField(String textFieldInput) {
9. commit(textFieldInput);
10. }
12. public void commit(String input){
13. consoleText.concat(input);
14. }
I am creating a Textfield called inputField, then instantiating it in my gui, then all i want is to pass the confirmed text (when you type then hit 'Enter') from inputField to my method that adds it to a string so i can display it in a Textarea.

not sure what the problem is exactly, there isn't a whole lot of code there for me to screw up. I found a couple others with this same error but they were dealing with multiples in a dropdownlist. any help would be great. thanks

[SOLVED] fisica joints not working

[1 Reply]
- 01-Jan-2012 08:42 AM
- Forum: Contributed Library Questions
so i am trying to get a simple distance joint sketch running and for some reason i can't get joints to show up or work. I've tried in processing 2.0a4 and 1.5.1. here is the code i'm trying to run:
1. import fisica.*;
3. FWorld world;
4. FBlob myBlob;
5. float frequency = 5;
6. float damping = 1;
7. FBox box;
8. FBox box2;
9. FBlob blob;
10. FDistanceJoint joint;
11. FDistanceJoint joint2;
13. void setup() {
14. size(960, 600);
15. Fisica.init(this);
16. world = new FWorld();
17. world.setEdges(255);
18. world.setGravity(0, 100);
19. world.setGrabbable(true);
21. box = new FBox(100, 100);
22. box.setStatic(true);
23. box.setPosition(width/3, height/3);
24. world.add(box);
26. box2 = new FBox(100, 100);
27. box2.setStatic(true);
28. box2.setPosition(width/1.5, height/3);
29. world.add(box2);
31. blob = new FBlob();
32. blob.setAsCircle(width/2, height/2, 60);
33. world.add(blob);
35. joint = new FDistanceJoint(box, blob);
36. joint.setDrawable(true);
37. //joint.setFrequency(frequency);
38. //joint.setDamping(damping);
39. joint.setStrokeWeight(2);
40. joint.setStroke(0);
41. world.add(joint);
43. joint2 = new FDistanceJoint(blob, box2);
44. joint2.setDrawable(true);
45. //joint2.setFrequency(frequency);
46. //joint2.setDamping(damping);
47. joint2.setStrokeWeight(2);
48. joint2.setStroke(0);
49. world.add(joint2);
50. }
52. void draw() {
53. background(255);
54. world.step();
55. world.draw();
56. }
Should be simple enough, gravity and everything else seems to work with fisica but not joints, i used the examples provided with fisica as reference but i don't know if it's me and i'm missing something or if there is something else going on. any help would be greatly appreciated.

changing the angle of an orbiting object in relation to the x-axis

[4 Replies]
- 09-Nov-2011 10:44 PM
- Forum: Programming Questions
so i have an object rotating in 3d space around another object. i have it orbiting at an angle (45 deg from the -x axis it looks like). but i want to change the angle at which it orbits in relation to the x-axis, effectively making the orbit either more horizontal or more vertical while looking down the z-axis. does anyone know how to go about doing this? here is the code im using to do the orbit:

CODE:
1. public void orbit() {
2. theta += this.vel.x;
3. theta = fixAngle(theta, TWO_PI);
5. this.loc.x = this.origin.x+orbitRadius*cos(theta);
6. this.loc.y = this.origin.y+orbitRadius*cos(theta);
7. this.loc.z = this.origin.z+orbitRadius*sin(theta);
8. println(loc);
9. }
11. private float fixAngle(float ang, float range) {
12. if (ang < 0)
13. ang += range;
14. else if (ang > range)
15. ang -= range;
16. return ang;
17. }

GLGraphics and silhouette edges?

[1 Reply]
- 07-Nov-2011 02:31 PM
- Forum: Contributed Library Questions
is there any easy (relatively speaking) method to obtain silhouette edges or preform silhouette edge detection with GLGraphics or any of the other contributed libraries?

can't seem to access opengl constants

[5 Replies]
- 07-Nov-2011 09:27 AM
- Forum: Contributed Library Questions
does anyone know why i would get a "Cannot find anything named 'GL_ALL_ATTRIB_BITS'" error? im getting it on 2.0a3 and 1.5.1, here is the code i'm trying to run - its a modified version of the glslshader demo in GLGraphics examples:
1. void draw() {
2. background(250);
3. GLGraphics renderer = (GLGraphics)g;
4. renderer.beginGL();
6. // Push the GL attribute bits so that we don't wreck any settings
7. glPushAttrib(GL_ALL_ATTRIB_BITS);
9. // Enable polygon offsets, and offset filled polygons forward by 2.5
10. glEnable(GL_POLYGON_OFFSET_FILL);
11. glPolygonOffset(-2.5f, -2.5f);
13. // Set the render mode to be line rendering with a thick line width
14. glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
15. glLineWidth(3.0f);
17. // Set the colour to be white
18. glColor3f(1.0f, 1.0f, 1.0f);
20. // Set the polygon mode to be filled triangles
21. glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
22. glEnable(GL_LIGHTING);
24. // Set the colour to the background
25. glColor3f(0.0f, 0.0f, 0.0f);
27. // Pop the state changes off the attribute stack
28. // to set things back how they were
29. glPopAttrib();
30. renderer.endGL();
32. // The light is drawn after applying the translation and
33. // rotation trasnformations, so it always shines on the
34. // same side of the torus.
35. pointLight(0, 160, 255, -1, 0, 0);
36. lights();
38. // Centering the model in the screen.
39. translate(width/2, height/2, 0);
41. angle += 0.01;
42. rotateY(angle);
46. // Any geometry drawn between the shader's stop() and end() will be
47. // processed by the shader.
48. shader.start(); // Enabling shader.
50. renderer.model(torus);
51. shader.stop(); // Disabling shader.
53. }
it's the highlighted code im having trouble with. any help would be greatly appreciated.

it seems like camera objects are 'flattening' the image, opengl glsl cel shading (see images)

[3 Replies]
- 03-Nov-2011 07:49 PM
- Forum: Contributed Library Questions
so i am attempting to get a handle on cell shading using GLSLshader in GLGraphics. however whenever i add a camera (i've tried the processing camera, and peasycam) the image looses its depth and the model becomes almost all one color. see the picture below:

NO CAM (This is what i want the image to look like when using a camera view):

WITH P5 CAMERA:

WITH PEASYCAM:

im new to opengl and don't understand what's going on, can anyone help me figure it out?

Can't change color of the objects in the GLGraphics GLSL shader example

[1 Reply]
- 03-Nov-2011 02:55 PM
- Forum: Contributed Library Questions
for some reason i can't change the color of the torus in the GLSLshader example see the code below:
1. // Example of GLSL shader with GLGraphics.
2. // Adapted from Vitamin's shaderlib:
3. // http://www.pixelnerve.com/processing/libraries/shaderlib/
4. // More online resources about GLSL:
5. // http://nehe.gamedev.net/data/articles/article.asp?article=21
6. // http://zach.in.tu-clausthal.de/teaching/cg_literatur/glsl_tutorial/index.html
8. import processing.opengl.*;
9. import codeanticode.glgraphics.*;
11. GLModel torus;
12. GLSLShader shader;
13. float angle;
15. void setup() {
16. size(800, 600, GLConstants.GLGRAPHICS);
18. torus = createTorus(100, 50, 20, 500, 0, 0, 255, 255, "");
20. // Loading toon shader. Taken from here:
21. // http://www.lighthouse3d.com/opengl/glsl/index.php?toon3
22. shader = new GLSLShader(this, "toonvert.glsl", "toonfrag.glsl");
23. }
25. void draw() {
26. GLGraphics renderer = (GLGraphics)g;
27. renderer.beginGL();
29. background(0);
31. lights();
33. // Centering the model in the screen.
34. translate(width/2, height/2, 0);
36. angle += 0.01;
37. rotateY(angle);
39. // The light is drawn after applying the translation and
40. // rotation trasnformations, so it always shines on the
41. // same side of the torus.
42. pointLight(0, 160, 255, 0, 600, 400);
44. shader.start(); // Enabling shader.
45. // Any geometry drawn between the shader's stop() and end() will be
46. // processed by the shader.
47. torus.setColors(0, 160, 255, 255);
48. renderer.model(torus);
50. shader.stop(); // Disabling shader.
52. renderer.endGL();
53. }
55. GLModel createTorus(float outerRad, float innerRad, int numc, int numt, int r, int g, int b, int a, String texName) {
56. GLModel model;
57. GLTexture tex;
59. ArrayList vertices = new ArrayList();
60. ArrayList normals = new ArrayList();
61. ArrayList texcoords = new ArrayList();
63. float x, y, z, s, t, u, v;
64. float nx, ny, nz;
65. float a1, a2;
66. int idx = 0;
67. for (int i = 0; i < numc; i++) {
68. for (int j = 0; j <= numt; j++) {
69. for (int k = 1; k >= 0; k--) {
70. s = (i + k) % numc + 0.5;
71. t = j % numt;
72. u = s / numc;
73. v = t / numt;
74. a1 = s * TWO_PI / numc;
75. a2 = t * TWO_PI / numt;
77. x = (outerRad + innerRad * cos(a1)) * cos(a2);
78. y = (outerRad + innerRad * cos(a1)) * sin(a2);
79. z = innerRad * sin(a1);
81. nx = cos(a1) * cos(a2);
82. ny = cos(a1) * sin(a2);
83. nz = sin(a1);
85. vertices.add(new PVector(x, y, z));
86. normals.add(new PVector(nx, ny, nz));
87. texcoords.add(new PVector(u, v));
88. }
89. }
90. }
92. model = new GLModel(this, vertices.size(), QUAD_STRIP, GLModel.STATIC);
93. model.updateVertices(vertices);
95. if (texName != null && !texName.equals("")) {
96. tex = new GLTexture(this, texName);
97. model.initTextures(1);
98. model.setTexture(0, tex);
99. model.updateTexCoords(0, texcoords);
100. }
102. model.initNormals();
103. model.updateNormals(normals);
105. model.initColors();
106. model.setColors(r, g, b, a);
108. return model;
109. }
can anyone help me figure this out? i've tried changing the pointLight color, the input values for the torus and tried hard coding in a color in the torus class. any help would be greatly appreciated

don't know why a ClassNotFoundException: com.sun.opengl.cg.CGcontext error is being thrown

[5 Replies]
- 03-Nov-2011 02:26 PM
- Forum: Contributed Library Questions
here's the error:
1. Exception in thread "Animation Thread" java.lang.NoClassDefFoundError: com/sun/opengl/cg/CGcontext
2. at codeanticode.glgraphics.GLSLShader.<init>(Unknown Source)
3. at Atomos3.setup(Atomos3.java:116)
4. at processing.core.PApplet.handleDraw(PApplet.java:1866)
5. at processing.core.PApplet.run(PApplet.java:1788)
6. at java.lang.Thread.run(Thread.java:680)
7. Caused by: java.lang.ClassNotFoundException: com.sun.opengl.cg.CGcontext
8. at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
9. at java.security.AccessController.doPrivileged(Native Method)
10. at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
11. at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
12. at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
13. at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
14. ... 5 more
heres the important code:
1. import processing.opengl.*;
2. import javax.media.opengl.*;
3. import codeanticode.glgraphics.*;
5. GLSLShader shader;
7. //public String sketchRenderer() {
8. // return P3D;
9. //}
11. void setup() {
12. size(960, 600, P3D);
13. sphereDetail(12);
15. shader = new GLSLShader(this);
16. shader.loadVertexShader("toonvert.glsl");
17. shader.loadFragmentShader("toonfrag.glsl");
18. }
20. void draw() {
21. background(0);
22. directionalLight(0, 50, 200, 0, 0, 100);
23. directionalLight(200, 0, 25, 0, 0, -100);
25. GLGraphics renderer = (GLGraphics)g;
26. renderer.beginGL();
29. lights();
30. shader.start();
32. translate(width/2, height/2, 0);
33. sphere(100);
34. shader.stop(); // Disabling shader.
36. renderer.endGL();
37. }
anyone have an idea as to why this code would throw that error?

cel-shading or an equivalent effect

[1 Reply]
- 02-Nov-2011 09:52 PM
- Forum: General Discussion
does anyone know of any processing based resources?

wrong length of pixels array error but the lengths are the same

[1 Reply]
- 02-Nov-2011 07:48 PM
- Forum: Core Library Questions
I am getting this error:
1. Exception in thread "Animation Thread" java.lang.RuntimeException: PTexture: wrong length of pixels array
2. at processing.opengl.PTexture.set(PTexture.java:246)
3. at processing.opengl.PGraphicsOpenGL.updateTexture(PGraphicsOpenGL.java:6972)
4. at processing.opengl.PGraphicsOpenGL.getTexture(PGraphicsOpenGL.java:6941)
5. at processing.opengl.PGraphicsOpenGL.renderTriangles(PGraphicsOpenGL.java:2702)
6. at processing.opengl.PGraphicsOpenGL.endShape(PGraphicsOpenGL.java:1962)
7. at processing.core.PGraphics.endShape(PGraphics.java:1376)
8. at processing.core.PGraphics.imageImpl(PGraphics.java:3159)
9. at processing.core.PGraphics.image(PGraphics.java:3015)
10. at processing.core.PApplet.image(PApplet.java:10664)
11. at Atomos_v1_0$Atom.display(Atomos_v1_0.java:70)
12. at Atomos_v1_0.draw(Atomos_v1_0.java:32)
13. at processing.core.PApplet.handleDraw(PApplet.java:1891)
14. at processing.core.PApplet.run(PApplet.java:1788)
15. at java.lang.Thread.run(Thread.java:680)
however my code is telling me that the w*h of my PGraphics object and the length of the pixels array is the same see the code below:
1. Atom atom;
3. public void setup(){
4. size(960, 600, P3D);
5. color c = color(14, 147, 193);
6. atom = new Atom(new PVector(width/2, height/2), new PVector(0, 0), 150, c);
8. }
10. public void draw(){
11. background(100);
12. atom.display();
13. }
15. public class Atom{
17. PVector loc, vel;
18. int size;
19. color atomColor;
20. PGraphics pg;
22. Atom(PVector _loc, PVector _vel, int _size, color _atomColor){
23. this.loc = _loc;
24. this.vel = _vel;
25. this.size = _size;
26. this.atomColor = _atomColor;
27. this.pg = new PGraphics();
28. this.pg = createGraphics(this.size, this.size, P2D);
29. this.pg.beginDraw();
30. PVector center = new PVector(this.size/2, this.size/2);
32. for(int x = 0; x <= this.size; x++){
33. for(int y = 0; y <= this.size; y++){
34. PVector point = new PVector(x, y);
35. float distance = PVector.dist(center, point);
36. float maxDist = this.pg.width/2;
37. float distCoeff = map(distance, 0, maxDist, 255, 0);
38. int thisColor = color(this.atomColor, distCoeff);
39. this.pg.set(x, y, thisColor);
40. println("("+x+", "+y+") = "+"("+red(thisColor)+", "+green(thisColor)+", "+blue(thisColor)+")");
41. }
42. }
43. this.pg.loadPixels();
44. println(this.size*this.size);
45. println(this.pg.pixels.length);
46. pg.endDraw();
47. }
49. public void display(){
50. imageMode(CENTER);
51. image(this.pg, this.loc.x, this.loc.y);
52. }
53. }
and i get this output:
1. ...
2. (149, 147) = (0.0, 0.0, 0.0)
3. (149, 148) = (0.0, 0.0, 0.0)
4. (149, 149) = (0.0, 0.0, 0.0)
5. 22500
6. 22500
i read about an issue with the PTexture error on the processing googlecode site here: http://code.google.com/p/processing/issues/detail?id=829. It says that it has been resolved however i'm getting the error on 2.0a1. anyone know how i can use 2d graphics on a 3d view...if that makes any sense

making things glow like in the metaball example

[5 Replies]
- 24-Oct-2011 03:21 PM
- Forum: Core Library Questions
can someone explain how the glow effect in the metaball example works? i've been through it again and again but i can't seem to make heads nor tails of it.
/**

* Metaball Demo Effect

* by luis2048.

*

* Organic-looking n-dimensional objects. The technique for rendering

* metaballs was invented by Jim Blinn in the early 1980s. Each metaball

* is defined as a function in n-dimensions.

*/

int numBlobs = 3;

int[] blogPx = { 0, 90, 90 };

int[] blogPy = { 0, 120, 45 };

// Movement vector for each blob

int[] blogDx = { 1, 1, 1 };

int[] blogDy = { 1, 1, 1 };

PGraphics pg;

int[][] vy,vx;

void setup() {

size(640, 360);

pg = createGraphics(160, 90, P2D);

vy = new int[numBlobs][pg.height];

vx = new int[numBlobs][pg.width];

}

void draw() {

for (int i=0; i<numBlobs; ++i) {

blogPx[i]+=blogDx[i];

blogPy[i]+=blogDy[i];

// bounce across screen

if (blogPx[i] < 0) {

blogDx[i] = 1;

}

if (blogPx[i] > pg.width) {

blogDx[i] = -1;

}

if (blogPy[i] < 0) {

blogDy[i] = 1;

}

if (blogPy[i] > pg.height) {

blogDy[i]=-1;

}

for (int x = 0; x < pg.width; x++) {

vx[i][x] = int(sq(blogPx[i]-x));

}

for (int y = 0; y < pg.height; y++) {

vy[i][y] = int(sq(blogPy[i]-y));

}

}

// Output into a buffered image for reuse

pg.beginDraw();

pg.loadPixels();

for (int y = 0; y < pg.height; y++) {

for (int x = 0; x < pg.width; x++) {

int m = 1;

for (int i = 0; i < numBlobs; i++) {

// Increase this number to make your blobs bigger

m += 60000/(vy[i][y] + vx[i][x]+1);

}

pg.pixels[x+y*pg.width] = color(0, m+x, (x+m+y)/2);

}

}

pg.updatePixels();

pg.endDraw();

// Display the results

image(pg, 0, 0, width, height);

}

parsing *usable* code from a txt or xml file

[1 Reply]
- 25-Sep-2011 03:34 PM
- Forum: Programming Questions
is it possible to pull string elements from a txt or xml to use as code in the sketch running the txt/xml parsing?
for example, imagine a game with multiple levels and each level's code for it's attributes and enemies and items and map, etc. are put in a txt or xml file. Then i would take the txt/xml file parse out each line or node and use the code in a running sketch.

PFont in android mode.

[1 Reply]
- 18-Sep-2011 06:28 PM
- Forum: Android Processing
I am getting this error, with no text showing:
1. PGraphics: Using inefficient font rendering.
2. java.lang.Exception
3. at processing.core.PGraphics.textLineImpl(PGraphics.java:3140)
4. at processing.core.PGraphicsAndroid3D.textLineImpl(PGraphicsAndroid3D.java:3516)
5. at processing.core.PGraphics.textLineAlignImpl(PGraphics.java:3130)
6. at processing.core.PGraphics.text(PGraphics.java:2837)
7. at processing.core.PApplet.text(PApplet.java:7475)
8. at processing.android.test.atomos.Atomos.draw(Atomos.java:70)
9. at processing.core.PApplet.handleDraw(PApplet.java:1865)
10. at processing.core.PGraphicsAndroid3D$A3DRenderer.onDrawFrame(PGraphicsAndroid3D.java:7709)
11. at android.opengl.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:1116)
12. at android.opengl.GLSurfaceView$GLThread.run(GLSurfaceView.java:975)
has anyone had and success implementing text into a sketch in android mode?

spherical orbiting - rotation doing something strange

[2 Replies]
- 14-Sep-2011 09:30 AM
- Forum: Core Library Questions
so i have been trying to perfect spherical orbiting, what i have is a sphere located at (0, 0, 0), and a camera that rotates around it in a...spherical way. i can make rotations in the x-z plane (around) just fine but when it comes to rotating in the y-z plane (rotating towards the top or bottom of something, not around) it bugs out and won't rotate properly. I am trying to achieve the same effect as peasycam minus the enertia and fancy stuff. here is my code:
1. import processing.opengl.*;
2. PVector cam;
3. float camRadius, camTheta, camPhi;
4. private final static float compensation = 0.05f;
5. void setup() {
6. size(500, 500, OPENGL);
7. hint(ENABLE_OPENGL_4X_SMOOTH);
8. hint(DISABLE_DEPTH_TEST);
9. cam = new PVector();
10. camRadius = 250.0f;
11. camTheta = 70.0f;
12. camPhi = -25.0f;
13. updateCamera();
14. }
15. void draw() {
16. background(255);
17. lights();
18. if (mousePressed) {
19. camTheta += (mouseX-pmouseX)*compensation;
20. camPhi += (mouseY-pmouseY)*compensation;
21. println(camPhi);
22. }
23. updateCamera();
24. camera(cam.x, cam.y, cam.z, 0, 0, 0, 0, 1, 0);
26. sphereDetail(15);
27. fill(255);
28. stroke(255);
29. sphere(25);
30. }
31. public void updateCamera() {
32. cam.x = camRadius * sin(camTheta)*sin(camPhi);
33. cam.y = camRadius * -cos(camPhi);
34. cam.z = camRadius * -cos(camTheta)*sin(camPhi);
35. redraw();
36. }
can anyone help me figure this out?

need help with spherical orbiting

[1 Reply]
- 12-Sep-2011 10:46 AM
- Forum: Programming Questions
i am trying to make the camera orbit spherically and have modified an example about orbiting on one plane (the x-z plane to exact) this is what i have so far:
1. float xrotation=0;
2. float yrotation=0;
3. void setup() {
4. size(500, 500, P3D);
5. background(255);
6. }
7. void draw() {
8. background(255);
9. lights();
10. xrotation += mouseX-pmouseX;
11. yrotation += mouseY-pmouseY;
12. float orbitRadius= 200;
13. float ypos= sin(radians(yrotation))*orbitRadius;
14. float xpos= cos(radians(xrotation))*orbitRadius;
15. float zpos= sqrt((orbitRadius*orbitRadius-xpos*xpos-ypos*ypos));
17. camera(xpos, ypos, zpos, 0, 0, 0, 0, -1, 0);
18. box(25);
19. }
now sometimes the box disappears and im not sure why i may not have the right equation for ypos but the other two should be solid... i think lol. does anyone know why this might be happening>?

spherical movement of camera based on mouse movement

[4 Replies]
- 10-Sep-2011 08:34 AM
- Forum: Programming Questions
i am trying to figure out how i can move the basic camera rig in manner that would have it able to move to any point along a sphere all while looking at a central point (i.e. the center of the scene would be (0, 0, 0)). I'm pretty sure i need to use spherical coordinates but I'm not sure how to implement the equations. any help would be greatly appreciated.

PeasyCam and Processing for Android

[2 Replies]
- 07-Sep-2011 06:00 AM
- Forum: Android Processing
is there a way to implement PeasyCam (or perhaps another camera library) for Processing for Android? I noticed that whenever i try to run an android sketch, even the peasycam example, i get this error:
1. java.lang.NoClassDefFoundError: peasy.PeasyCam$PeasyMousewheelListener
2. at peasy.PeasyCam.<init>(Unknown Source)
3. at peasy.PeasyCam.<init>(Unknown Source)
4. at processing.android.test.hellopeasy.HelloPeasy.setup(HelloPeasy.java:25)
5. at processing.core.PApplet.handleDraw(PApplet.java:1783)
6. at processing.core.PGraphicsAndroid3D$A3DRenderer.onDrawFrame(PGraphicsAndroid3D.java:7358)
7. at android.opengl.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:1363)
8. at android.opengl.GLSurfaceView$GLThread.run(GLSurfaceView.java:1118)
any suggestions?

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