Processing Forum

Semi-transparency in GLGraphics

[4 Replies]
- 20-Jul-2012 08:09 AM
- Forum: Contributed Library Questions
Hi everyone,

I'm still pretty new to GLGraphics and I just wanted to ask what the best way to create a semi-transparent shape was. I have rendered a sphere based on the globe example, but need to be able to see through it to an extent.

Should I then just apply colours with an alpha value to each vertex, or do I need to use a sprite or texture or something which is semitransparent? I'm after a very basic example or explanation. This sphere must be a GLModel.

And then how should I combine rendering that sphere with rendering other lines/point/shape GLModels which surround the sphere which may or may not be semi-transparent themselves? Blending modes and depth masking etc

Thanks!

GLGraphics and strange problems with matrix transformations

[4 Replies]
- 16-Jul-2012 06:44 AM
- Forum: Contributed Library Questions
Hi,

I'm sure there's a simple solution to this, but I have a series of shapes involving a bunch of matrix transformations (translate, rotateX, rotateY and rotateZ, pushMatrix and popMatrix) which draw fine outside of the beginGL() / endGL() block, and I then draw a GLModel on top of that which is inside beginGL() / endGL(). But if I put beginGL() / endGL() around everything in the draw function then suddenly everything goes c-rrazy.... though you'll notice the red dots (the GLModel) are in the same spot

I tried changing everything to renderer.translate(), renderer.rotateX(), renderer.pushMatrix() etc, but no help.

Here are two screenshots.

Any ideas?

Slow framerates and slowdown

[6 Replies]
- 03-Jul-2012 05:43 AM
- Forum: Core Library Questions
Hey everyone,

I'm working on a project at the moment with lots and lots of data, reading from a text file. The problem I'm having is really low framerates and then a slowdown - starting on 9fps and then getting slower and slower, tending towards 0fps. The points are being plotted with an opengl vertex buffer object (but this isn't the problem, the framerate was the same before I switched to opengl calls).

VisualVM blames my function drawData(). The code for the entire class that function is in is below. Is there a gaping problem here? Is a slowdown a sign of a bad loop or something, or does it just happen if it's all too much?
1. //This is GOD, the class for a Geospatially Overlaid Dataset.
2. //It takes a data input, parses it and draws it.
4. class GOD {
6. private String name;
7. private String source;
8. private String path;
9. private String filetype;
10. private String seperator;
11. private int fieldCount;
12. private HashMap metaValues;
13. private XMLElement metaData;
14. private String[][] godLayerData;
15. private int datasetSize;
16. FloatBuffer vertexBuffer;
17. FloatBuffer colourBuffer;
19. GOD(XMLElement GODLayer) {
20. metaData = GODLayer;
21. loadData();
22. initialiseOpenGLBuffer();
23. }
25. void getMetadata() {
27. name = metaData.getChild("name").getContent();
28. source = metaData.getChild("source").getContent();
29. path = metaData.getChild("path").getContent();
30. filetype = metaData.getChild("filetype").getContent();
31. seperator = metaData.getChild("seperator").getContent();
32. fieldCount = metaData.getChild("values").getChildCount();
33. metaValues = new HashMap(fieldCount, 1);
34. for (int i=0;i<fieldCount;i++) {
35. metaValues.put(metaData.getChild("values").getChild(i).getContent(), str(i));
36. }
37. }
39. void loadData() {
41. getMetadata();
43. if (filetype==null) {
44. println("filetype for "+name+" is either not set or caught");
45. }
46. else if (filetype!=null) {
48. if (filetype.equals("csv")) {
49. String[] rawLines = loadStrings(path);
50. int ii=rawLines.length;
51. datasetSize = ii-1;
52. godLayerData = new String[datasetSize][fieldCount];
53. for (int i=1;i<ii;i++) {
54. String[] splitLine = split(rawLines[i], seperator);
55. for (int j=0;j<fieldCount;j++) {
56. godLayerData[i-1][j] = splitLine[j];
57. }
58. }
59. }
60. else {
61. println("filetype '"+filetype+"' is not recognised");
62. }
63. }
64. }
66. void initialiseOpenGLBuffer() {
67. vertexBuffer = BufferUtil.newFloatBuffer(datasetSize*3); //space in the buffer for x,y,z positions
68. colourBuffer = BufferUtil.newFloatBuffer(datasetSize*4); //space in the buffer for r,g,b,a values
69. for (int i = 0; i < datasetSize; i++) {
70. // r,g,b,a
71. colourBuffer.put(1);
72. colourBuffer.put(0);
73. colourBuffer.put(0);
74. colourBuffer.put(0.4);
75. }
76. colourBuffer.rewind();
77. PGraphicsOpenGL pgl = (PGraphicsOpenGL) g;
78. GL gl = pgl.beginGL();
79. gl.glEnableClientState(GL.GL_VERTEX_ARRAY);
80. gl.glVertexPointer(3, GL.GL_FLOAT, 0, vertexBuffer);
81. gl.glEnableClientState(GL.GL_COLOR_ARRAY);
82. gl.glColorPointer(4, GL.GL_FLOAT, 0, colourBuffer);
83. gl.glPointSize(1);
84. pgl.endGL();
85. }
88. void drawData() {
89. int latitudeIndex = int(metaValues.get("latitude").toString());
90. int longitudeIndex = int(metaValues.get("longitude").toString());
91. for (int j=datasetSize-1;j>-1;j--) {
92. float latitude = float(godLayerData[j][latitudeIndex]);
93. float longitude = float(godLayerData[j][longitudeIndex]);
95. PVector spaceLoc = equator.returnGlobeCoordinate(latitude, longitude);
96. vertexBuffer.put(spaceLoc.x);
97. vertexBuffer.put(spaceLoc.y);
98. vertexBuffer.put(spaceLoc.z);
99. }
100. vertexBuffer.rewind();
101. PGraphicsOpenGL pgl = (PGraphicsOpenGL) g;
102. GL gl = pgl.beginGL();
103. gl.glColorPointer(4, GL.GL_FLOAT, 0, colourBuffer);
104. gl.glVertexPointer(3, GL.GL_FLOAT, 0, vertexBuffer);
105. gl.glDrawArrays(GL.GL_POINTS, 0, datasetSize);
106. pgl.endGL();
107. }
108. }
The PVector function is also here below, maybe the problem is in the maths here:
1. PVector returnGlobeCoordinate(float latitude, float longitude) {
3. float lat = latitude;
4. float lng = longitude;
5. lat = radians(lat);
6. lng = radians(lng);
8. float pX = pRadius * cos(lat) * cos(lng);
9. float pY = pRadius * sin(lat);
10. float pZ = pRadius * cos(lat) * sin(lng);
12. PVector outputPVector = new PVector(int(pX), int(pY), int(pZ));
13. return outputPVector;
14. }
datasetSize is about 2,000,000 for one of the datasets (20 for the only other one currently in there). Is that just too much for a loop to run every frame? But then why does it get slower and slower? Or is it just graphics? surely 2,000,000 points should be able to render faster than this, especially when I'm using a vertex buffer object?

Thanks so much!

Converting String to float from 2D array

[7 Replies]
- 27-Jun-2012 12:42 PM
- Forum: Contributed Library Questions
I have a csv file with rows of data, some of it numbers, some of it text. I'm trying to store this data in a String[][], access it later and then convert it into a useful format.

There is another question with a similar problem/title, except their problem was solved by converting the entire String array into a float array. However, my String array does not contain only floats. It has text in it as well. I can access an individual value from my String[][] and print it fine, but converting it to a float produces this error:
2. Exception in thread "Animation Thread" java.lang.NullPointerException
3. at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:989)
4. at java.lang.Float.valueOf(Float.java:388)
5. at java.lang.Float.<init>(Float.java:489)
6. at processing.core.PApplet.parseFloat(PApplet.java:6566)
7. at processing.core.PApplet.parseFloat(PApplet.java:6561)
8. at GESUS$Planet.visualise(GESUS.java:526)
9. at GESUS$Planet.plot(GESUS.java:364)
10. at GESUS.draw(GESUS.java:105)
11. at processing.core.PApplet.handleDraw(PApplet.java:1631)
12. at processing.core.PApplet.run(PApplet.java:1530)
13. at java.lang.Thread.run(Thread.java:680)
The code is below.
2. // Welcome to GESUS
3. // Geospatial Earth Simulation Using Sound (SuperCollider)
5. import processing.opengl.*;
6. import javax.media.opengl.*; //use this elsewhere, but removed that code.
7. import tomc.gpx.*; //maybe there are conflicts with the libraries I am using?
8. import java.util.Calendar;
9. import java.util.TimeZone;
10. import java.lang.Math;
11. import java.io.File;
13. GL gl;
14. PGraphicsOpenGL pgl;
15. //Equator equator; //class used for solving equations, used elswhere but code removed
17. Planet earth;
18. public GPX planetGeography;
19. XMLElement godDirectory;
22. void setup() {
24. size(1600,1000,OPENGL);
25. background(0);
26. frameRate(300);
27. earth = new Planet();
28. getDataPaths();
29. }
31. void getDataPaths() {
32. godDirectory = new XMLElement(this,"godDirectory.xml");
33. int godCount = godDirectory.getChildCount();
34. for(int i=0;i<godCount;i++) {
35. XMLElement godLayer = godDirectory.getChild(i);
36. GOD GODLayer = new GOD(godLayer);
37. }
38. }
2. //This is GOD, the class for a Geospatially Overlaid Dataset.
3. //It takes a data input, parses it and is then called by the Planet to which it is assigned.
5. class GOD {
7. String name;
8. String source;
9. String path;
10. String filetype;
11. String seperator;
12. int fieldCount;
13. HashMap metaValues;
14. XMLElement metaData;
15. String[][] godLayerData;
16. ArrayList godLayer;
18. GOD(XMLElement GODLayer) {
19. metaData = GODLayer;
20. getMetadata();
21. loadData();
22. passData();
23. }
25. void getMetadata() {
27. name = metaData.getChild("name").getContent();
28. source = metaData.getChild("source").getContent();
29. path = metaData.getChild("path").getContent();
30. filetype = metaData.getChild("filetype").getContent();
31. seperator = metaData.getChild("seperator").getContent();
32. fieldCount = metaData.getChild("values").getChildCount();
33. godLayer = new ArrayList();
34. metaValues = new HashMap(fieldCount+1,1);
35. for (int i=0;i<fieldCount;i++) {
36. metaValues.put(metaData.getChild("values").getChild(i).getContent(),i);
37. }
38. }
40. void loadData() {
41. if (filetype==null) {
42. println("filetype for "+name+" is either not set or caught");
43. }
44. else if (filetype!=null) {
46. if (filetype.equals("txt")) {
47. String[] rawLines = loadStrings(path);
48. String[][] godLayerData = new String[rawLines.length][fieldCount];
49. for (int i=1;i<rawLines.length;i++) {
50. String[] splitLine = split(rawLines[i], seperator);
51. for (int j=0;j<metaValues.size();j++) {
52. godLayerData[i][j] = splitLine[j];
53. }
54. }
55. metaValues.put("datasetSize",rawLines.length-1);
56. godLayer.add(metaValues);
57. godLayer.add(godLayerData);
58. }
59. else if (filetype.equals("csv")) {
60. String[] rawLines = loadStrings(path);
61. String[][] godLayerData = new String[rawLines.length][fieldCount];
62. for(int i=1;i<rawLines.length;i++) {
63. String[] splitLine = split(rawLines[i], seperator);
64. for(int j=0;j<fieldCount;j++) {
65. godLayerData[i][j] = splitLine[j];
66. }
67. }
68. metaValues.put("datasetSize",rawLines.length-1);
69. godLayer.add(metaValues);
70. godLayer.add(godLayerData);
71. }
72. else {
73. println("filetype '"+filetype+"' is not recognised");
74. }
75. }
76. }
77. void passData() {
78. earth.put(godLayer);
79. }
80. }
earth is an instance of Planet, below (there might be some irrelevant variables, I use them in code not included):
2. class Planet {
3. float pRadius;
4. int pAspect;
5. int pLongitudeLineIncrement;
6. int pLatitudeLineIncrement;
7. int pDepth;
8. int pDarksideVisibility;
9. String pGeographyFile;
10. float pRotationVelocity;
11. PVector pCentrePoint;
12. float pSolarDeclination;
13. ArrayList godInputs;
15. Planet() {
16. pRadius = 2.0*int(min(height, width)*0.4);
17. pAspect = 0;
18. pLongitudeLineIncrement = 15;
19. pLatitudeLineIncrement = 15;
20. pDepth = 1000;
21. pCentrePoint = new PVector(width/2, height/2, -pDepth);
22. pDarksideVisibility = 150; //set the opacity of the darkside of the Earth (0-255)
23. pGeographyFile = "continents.gpx"; //GPX file containing the earth's geography
24. godInputs = new ArrayList();
25. }
27. void put(ArrayList input) {
28. if(input==null) {
29. println("data input is empty");
30. }
31. else {
32. godInputs.add(input);
33. }
34. }
36. void visualise() {
37. for(int i=0;i<godInputs.size();i++){
38. ArrayList godLayer = (ArrayList) godInputs.get(i);
39. HashMap godMetaData = (HashMap) godLayer.get(0);
40. String[][] godLayerData = (String[][]) godLayer.get(1);
41. int datasetSize = int(godMetaData.get("datasetSize").toString());
42. for(int j=0;j<datasetSize;j++) {
43. String latitude = godLayerData[j][int(godMetaData.get("latitude").toString())];
44. println(latitude); //this works absolutely fine!
45. //float latitudeFloat = float(latitude);
47. //why can i not convert this string into a float???
49. }
50. }
51. }
52. }
The weirdest part is that if you run this code as is, it prints latitudes out no problem. However, as soon as you uncomment the "float latitudeFloat = float(latitude);" line, it prints NULL followed by the error!!! Huh? How can handling a variable LATER affect it earlier in the program? Am I making a dumb mistake or is there something sinister going on?

Thanks in advance for the help, and if there are any other tips on how to make this work better I'd love to hear them!

UTC time down to milliseconds

[2 Replies]
- 16-May-2012 06:57 AM
- Forum: General Discussion
Hi Everyone,

I'm creating a program which requires millisecond precision. It maps realtime global events, so I also need that time in UTC/GMT time. I created some bloated class which converted my system time into UTC (but I had to manually input my timezone - and this program will eventually be running on the web so that's not workable) with milliseconds from millis() minus the milliseconds after a second change that the program started... blah blah ... its basically crap...

...so long story short, how can I use java's date format/simple date format/calendar/whatever? I read some stuff about parts of it being outdated, plus I don't understand some of the terminology. Does anyone know how to just simply query the current UTC time with millisecond precision?

Thanks for your help!

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