Image not rendering on web browser - html

I got a kaleidoscope code from Gary George at openprocessing. I tried to modify it to meet my needs and export it to web. But I'm having trouble rendering the image on the browser. It runs well on the desktop but not on browser. I've been trying to fix the error but...no luck (yet, I hope).
Here is the code:
/**
* Kaleidoscope by Gary George.
*
*Load an image.
*Move around the mouse to explore other parts of the image.
*Press the up and down arrows to add slices.
*Press s to save.
*
*I had wanted to do a Kaleidoscope and was inspired with the by Devon Eckstein's Hexagon Stitchery
*and his use of Mask. His sketch can be found at http://www.openprocessing.org/visuals/?visualID=1288
*/
PImage a;
int totalSlices=8; // the number of slices the image will start with... should be divisable by 4
int previousMouseX, previousMouseY; //store previous mouse coordinates
void setup()
{
size(500,500, JAVA2D);
background(0,0,0);
smooth(); //helps with gaps inbetween slices
fill(255);
frameRate(30);
a=loadImage("pattern.jpg");
}
void draw() {
if(totalSlices==0){
background(0,0,0);
image(a,0,0);
}
else{
if(mouseButton == LEFT){
background(0,0,0);
//the width and height parameters for the mask
int w =int(width/3.2);
int h = int(height/3.2);
//create a mask of a slice of the original image.
PGraphics selection_mask;
selection_mask = createGraphics(w, h, JAVA2D);
selection_mask.beginDraw();
selection_mask.smooth();
selection_mask.arc(0,0, 2*w, 2*h, 0, radians(360/totalSlices+.1)); //using 369 to reduce lines on arc edges
selection_mask.endDraw();
float wRatio = float(a.width-w)/float(width);
float hRatio = float(a.height-h)/float(height);
//println("ratio: "+hRatio+"x"+wRatio);
PImage slice = createImage(w, h, RGB);
slice = a.get(int((mouseX)*wRatio), int((mouseY)*hRatio), w, h);
slice.mask(selection_mask);
translate(width/2,height/2);
float scaleAmt =1.5;
scale(scaleAmt);
for(int k = 0; k<=totalSlices ;k++){
rotate(k*radians(360/(totalSlices/2)));
image(slice, 0, 0);
scale(-1.0, 1.0);
image(slice,0,0);
}
}
resetMatrix();
}
}

You need to change two things for loading a local image in JS mode:
Your images must be in a folder called data inside your sketch folder. You can just make the folder yourself and put the image in it. You still load the image as before, no need to specify the data folder.
In JS mode, you need to preload the image using this command: /* #pjs preload="pattern.jpg"; */
So your full image loading code would be:
/* #pjs preload="pattern.jpg"; */
a = loadImage("pattern.jpg");

Related

How does a computer resize an image?

Image resizing is nearly universal in any GUI framework. In fact, one of the first things you learn when starting out in web development is how to scale images using CSS or HTML's img attributes. But how does this work?
When I tell the computer to scale a 500x500 img to 100x50, or the reverse, how does the computer know which pixels to draw from the original image? Lastly, is it reasonably easy for me to write my own "image transformer" in another programming language without significant drops in performance?
Based on a bit of research, I can conclude that most web browser will use nearest neighbor or linear interpolation for image resizing. I've written a concept nearest neighbor algorithm that successfully resizes images, albeit VERY SLOWLY.
using System;
using System.Drawing;
using System.Timers;
namespace Image_Resize
{
class ImageResizer
{
public static Image Resize(Image baseImage, int newHeight, int newWidth)
{
var baseBitmap = new Bitmap(baseImage);
int baseHeight = baseBitmap.Height;
int baseWidth = baseBitmap.Width;
//Nearest neighbor interpolation converts pixels in the resized image to pixels closest to the old image. We have a 2x2 image, and want to make it a 9x9.
//Step 1. Take a 9x9 image and shrink it back to old value. To do this, divide the new width by old width (i.e. 9/2 = 4.5)
float widthRatio = (float)baseWidth/newWidth;
float heightRatio = (float)baseHeight/newHeight;
//Step 2. Perform an integer comparison for each pixel in old I believe. If we have a pixel in the new located at (4,5), then the proportional will be
//(.8888, 1.11111) which SHOULD GO DOWN to (0,1) coordinates on a 2x2. Seems counter intuitive, but imagining a 2x2 grid, (4.5) is on the left-bottom coordinate
//so it makes sense the to be on the (0,1) pixel.
var watch = new System.Diagnostics.Stopwatch();
watch.Start();
Bitmap resized = new Bitmap(newWidth, newHeight);
int oldX = 0; int oldY = 0;
for (int i = 0; i < newWidth; i++)
{
oldX = (int)(i*widthRatio);
for (int j = 0; j < newHeight; j++)
{
oldY = (int)(j*heightRatio);
Color newColor = baseBitmap.GetPixel(oldX,oldY);
resized.SetPixel(i,j, newColor);
}
}
//This works, but is 100x slower than standard library methods due to GetPixel() and SetPixel() methods. The average time to set a 1920x1080 image is a second.
watch.Stop();
Console.WriteLine("Resizing the image took " + watch.Elapsed.TotalMilliseconds + "ms.");
return resized;
}
}
class Program
{
static void Main(string[] args)
{
var img = Image.FromFile(#"C:\Users\kpsin\Pictures\codeimage.jpg");
img = ImageResizer.Resize(img, 1000, 1500);
img.Save(#"C:\Users\kpsin\Pictures\codeimage1.jpg");
}
}
}
I do hope that someone else can come along and provide either a) a faster algorithm for nearest neighbor because I'm overlooking something silly, or b) another way that image scalers work that I'm not aware of. Otherwise, question... answered?

LIBGDX - How to get rid of banding effect on gradient background?

I am having banding issues with gradient related textures in my game and I can't seem to find what's the cause and how to solve it.
Here's what I am talking about: On the left is a gradient in my game, whereas on the right is a gradient generated in a gradient generator application(Tint). We can clearly see banding issues.
To create my gradient, I used this code to generate a Texture used to create an Image that I scale to fill the user's screen.
Pixmap pix = new Pixmap(2, 2, Pixmap.Format.RGBA8888);
pix.setColor(colorSchemes[backgroundColorScheme.ordinal()].getTopColor());
pix.fillRectangle(0,0,2,1);
pix.setColor(colorSchemes[backgroundColorScheme.ordinal()].getBottomColor());
pix.fillRectangle(0,1,2,1);
Texture texture = new Texture(pix);
texture.setFilter(Texture.TextureFilter.Linear,
Texture.TextureFilter.Linear);
pix.dispose();
I also have another issue with banding when I try to add fog-like actors on top of the background to animate it a bit. I scale them, change their opacity and move them around and again I get banding issues as highlighted in the picture below.
I am trying to replicate a background effect like in this game
https://www.youtube.com/watch?v=_vBczzj3NAU
I have this code in my render screen render loop:
#Override
public void render (float delta) {
Gdx.gl.glClearColor(0,0,0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
Gdx.gl.glEnable(GL20.GL_BLEND);
Gdx.gl.glBlendFunc(GL20.GL_SRC_ALPHA, GL20.GL_ONE_MINUS_SRC_ALPHA);
}
Any ideas on how I can solve those issues? Any help would be greatly appreciated.
Increasing the number of bits per color channel (I believe the default is 5 bits) to 8 bits fixed the banding problem for me.
In AndroidLauncher.java
AndroidApplicationConfiguration config = new AndroidApplicationConfiguration();
config.r = config.g = config.b = config.a = 8;
In DesktopLauncher.java
LwjglApplicationConfiguration config = new LwjglApplicationConfiguration();
config.r = config.g = config.b = config.a = 8;

Linking buttons to imported information from csv file

I would like to ask some help turning this representation into something more interactive. Im working with Processsing latest version. The main idea is I have a table in excel, I imported it into processsing. So far so good. Displayed the values as bubbles. My problem is that would like to create buttons to See further details from each bubble. So, click a button A, the corresponding bubbleA would light up and display its specific value, according to the imported table. I dont know how to connect the button to each bubble, neither how to turn the bubble to its original state once the button is pressed again.
I`m not from the programming field, I just manage to get this far with info that I have found online, so the code must be pretty messed up. I was trying to use the libraries from Processing but I cant really understand how the controlP5 works.. I asssume the structure is way more advanced than what I can handle now.
So, if anyone can help me, I would appreciate it very much.
Table B_A_table;
//Bubble[] bubbles = new Bubble[29];
ArrayList<Bubble> bubbles = new ArrayList<Bubble>();
float scale = 3;
int c_verdeClaro = color(182,189,149);
import controlP5.*;
ControlP5 cp5;
PFont font;
PFont font1;
void setup() {
size(1000, 1000);
colorMode(HSB,255);
loadData();
font = createFont("Verdana", 18);
font1 = createFont("Verdana Bold", 18);
//font = loadFont("Arial-Black-48.vlw");
//BEGIN TEST
cp5 = new ControlP5(this);
noStroke();
smooth();
//TEST
cp5 = new ControlP5(this);
ButtonBar b = cp5.addButtonBar("bar")
.setPosition(500, 0)
.setSize(400, 20)
.addItems(split("Man Woman 20s 30s 40s 50s µµ½É±Ç"," "))
;
println(b.getItem("Man"));
b.changeItem("a","text","first");
b.changeItem("b","text","second");
b.changeItem("c","text","third");
b.onMove(new CallbackListener(){
public void controlEvent(CallbackEvent ev) {
ButtonBar bar = (ButtonBar)ev.getController();
println("hello ",bar.hover());
}
});
//WND TEST
}
void draw() {
// Display all bubbles
background(0);
Graph_Bike_Aware_Experience_Sim();
//Graph_Bike_Uso_Satisf();
pushMatrix();
translate(400,500);
for (Bubble bubble : bubbles){
bubble.display();
}
popMatrix();
}
void loadData() {
// "header" indicates the file has header row. The size of the array
// is then determined by the number of rows in the table.
B_A_table = loadTable("BikeAwareExpr_Nao.csv", "header");
for (int i = 0; i<B_A_table.getRowCount(); i++) {
// Iterate over all the rows in a table.
TableRow row = B_A_table.getRow(i);
// Access the fields via their column name (or index).
float x = row.getFloat("awareness_x")*scale;
float y = row.getFloat("experi")*scale;
float d = row.getFloat("awareness_x")*0.2;
String n = row.getString("Awareness_Bike");
Float id = row.getFloat("ID");
// Make a Bubble object out of the data from each row.
bubbles.add(new Bubble(x, y, d, n,id));
//bubbles[i] = new Bubble(x, y, d, n);
}
}
// This simple Bubble class draws a circle to the window
// and displays a text label when the mouse hovers.
class Bubble {
float x, y;
float diameter;
String name;
Float id;
// Create the Bubble
Bubble(float tempX, float tempY, float tempD, String s, Float id) {
x = tempX;
y = tempY;
diameter = tempD;
name = s;
}
// Display the Bubble
void display() {
stroke(220);
strokeWeight(1);
noFill();
ellipse(x, y, diameter, diameter);
fill(200);
textFont(font,15);
textAlign(CENTER);
text(name, x,y);
}
}
void Graph_Bike_Aware_Experience_Sim(){
pushMatrix();
int tam_table = B_A_table.getRowCount();
translate(400,500);
stroke(150);
strokeWeight(1);
line( - 100 *scale, 0*scale, + 100*scale, 0*scale);
line(0*scale, - 100*scale, 0*scale, + 100*scale);
//fill(c_verdeClaro);
noStroke();
fill(255);
textFont(font,13);
text("Experience", 40 , -97*scale);
text("Awareness", -89*scale, -10);
fill(50);
//textFont(Arial-Black-48, 32);
text("0", 10,15);
pushMatrix();
fill(0);
textFont(font1,30 );
text("IDEAL", 80*scale , -120*scale);
fill(70);
textFont(font1,25 );
text("Bicycle", 0 , -110*scale);
popMatrix();
popMatrix();
}
/*void Graph_Bike_Uso_Satisf(){
pushMatrix();
int tam_table = B_A_table.getRowCount();
translate(900,400);
stroke(150);
strokeWeight(1);
line( - 100 *scale, 0*scale, + 100*scale, 0*scale);
line(0*scale, - 100*scale, 0*scale, + 100*scale);
//fill(c_verdeClaro);
noStroke();
c_verdeClaro_grad();
c_verdeEscuro_grad();
c_Vermelho_grad();
fill(255);
text("Experience", 40 , -97*scale);
text("Awareness", -89*scale, -10);
fill(0);
//textFont(Arial-Black-48, 32);
text("word", 10, 50);
text("IDEAL", 97*scale , -97*scale);
popMatrix();
}
*/
To handle this without Object Oriented Programing, or 'OOP' is a waste of time and code.
But relax OOP also referred to as "Objects" or " Classes". It is not that hard to get. In fact it is simple to learn, I mean, the basic stuff. And it makes things very easy.
In your case, you need to build an object to represent your data. Then you create several of them, populate with data, and all will be hold together. Kind of knowing it own business.
The usual example is
Class car
has those properties
color
plate
Then you can say:
Make a Blue, 3231 car!
Make a Red, 3001 car!
and so on...
When you need it you can ask, Blue car what's your plate, and it will know.
They can also have kind of "behaviours" known as functions or methods. Those do things, so you could say: "Red, turn right", or "Bubble, show me your data!" and they will OBEY you. :)
There is no point in trying to teach this hear though. There are TONs of great tutorials around. Use Duck Duck Go :) or google if you like.
This one here are from Processing's tutorials section itself. Great ones to begin with. :)

Setting a custom shader messes up the scale and position of a Sprite

I am using a custom shader on cocos2dx 3.1 trying to accomplish an special effect on a sprite used as a background (has to cover the whole screen)
However If i do not use the shader, the sprite is perfectly scaled and positioned, but when i do use it its show way smaller and on the bottom left.
Here is how i load the sprite
this->background_image = Sprite::create(image_name->GetText());
// Add background shader
if (this->background_image)
{
const GLchar *shaderSource = (const GLchar*) CCString::createWithContentsOfFile("OverlayShader.fsh")->getCString();
GLProgram * p = new GLProgram();
p->initWithByteArrays(ccPositionTextureA8Color_vert, shaderSource);
p->link();
p->updateUniforms();
this->background_image->setGLProgram(p);
}
// Classroom will be streched to cover all of the game screen
Size bgImgSize = this->background_image->getContentSize();
Size windowSize = Director::getInstance()->getWinSize();
float xScaleFactor = windowSize.width/bgImgSize.width;
float yScaleFactor = (windowSize.height-MARGIN_SPACE+10)/bgImgSize.height;
this->background_image->setScale(xScaleFactor, yScaleFactor);
this->background_image->setPosition(Vec2(windowSize.width/2.0f,windowSize.height/2.0f + ((MARGIN_SPACE-10)/2.0)));
this->background_image->retain();
And this is the shader im trying to use (a simple one, once this works ill change it to a photoshop-overlay style one)
varying vec4 v_fragmentColor;
varying vec2 v_texCoord;
void main()
{
vec4 v_orColor = v_fragmentColor * texture2D(CC_Texture0, v_texCoord);
float gray = dot(v_orColor.rgb, vec3(0.299, 0.587, 0.114));
gl_FragColor = vec4(gray, gray, gray, v_orColor.a);
}
My question is, what am i doing wrong? The first thing that comes to my mind is that the attribute pointers used on the vertex shader are not correct, but now i am using the default vertex shader.
I found the solution on another post, so i'll just quote it and link to that post:
Found the solution. The vert shader should not use the MVP matrix so I
loaded ccPositionTextureColor_noMVP_vert instead of
ccPositionTextureA8Color_vert.
Weird y-position offset using custom frag shader (Cocos2d-x)

How to draw smooth text in libgdx?

I try to draw simple text in my android game on libgdx, but it's look sharp. How to make text look smooth in different resolutions? My Code:
private BitmapFont font;
font = new BitmapFont();
font.scale((ppuX*0.02f));
font.draw(spb, "Score:", width/2-ppuX*2f, height-0.5f*ppuY);
font.getRegion().getTexture().setFilter(TextureFilter.Linear, TextureFilter.Linear);
This gets the texture used in a BitmapFont and changes its filtering to bilinear, allowing higher resulting image quality while both up- and downscaling it at the cost of slightly slower (the difference is usually not noticeable) GPU rendering.
One solution is to use the FreeType extension to libgdx, as described here. This allows you to generate a bitmap font on the fly from a .ttf font. Typically you would do this at startup time once you know the target resolution.
Here's an example:
int viewportHeight;
BitmapFont titleFont;
BitmapFont textFont;
private void createFonts() {
FileHandle fontFile = Gdx.files.internal("data/Roboto-Bold.ttf");
FreeTypeFontGenerator generator = new FreeTypeFontGenerator(fontFile);
FreeTypeFontParameter parameter = new FreeTypeFontParameter();
parameter.size = 12;
textFont = generator.generateFont(parameter);
parameter.size = 24;
titleFont = generator.generateFont(parameter);
generator.dispose();
}
You should definitly have a quick look on custom font shaders and/or DistanceField-Fonts. They're easy to understand and similarly easy to implement:
https://github.com/libgdx/libgdx/wiki/Distance-field-fonts
DistanceFieldFonts stay smooth, even when you upscale them:
Create a .fnt file using hiero which is provided by libgdx website.
Set the size of font to 150; it will create a .fnt file and a .png file.
Copy both files into your assets folder.
Now declare the font:
BitmapFont font;
Now in create method:
font = new BitmapFont(Gdx.files.internal("data/100.fnt"), false); // 100 is the font name you can give your font any name
In render:
font.setscale(.2f);
font.draw(batch, "whatever you want to write", x,y);
In general you don't get sharp text because you are designing your game for a certain resolution and when you move to a different device, Libgdx scales everything to match the new resolution. Even with linear filtering scaling is bad on text because round corners are easily distorted. In a perfect world you would create the content dynamically at runtime according to the number of pixels available to you and not a single automatic scale would be used.
This is the approach I'm using: Building everything for small screen (480 x 320), and when you open it on a bigger resolution, I load the BitmapFont with a higher size and apply and inverse scale to the one that Libgdx will later do automatically.
Here's an example to make things clearer:
public static float SCALE;
public static final int VIRTUAL_WIDTH = 320;
public static final int VIRTUAL_HEIGHT = 480;
public void loadFont(){
// how much bigger is the real device screen, compared to the defined viewport
Screen.SCALE = 1.0f * Gdx.graphics.getWidth() / Screen.VIRTUAL_WIDTH ;
// prevents unwanted downscale on devices with resolution SMALLER than 320x480
if (Screen.SCALE<1)
Screen.SCALE = 1;
FreeTypeFontGenerator generator = new FreeTypeFontGenerator(Gdx.files.internal("data/Roboto-Regular.ttf"));
// 12 is the size i want to give for the font on all devices
// bigger font textures = better results
labelFont = generator.generateFont((int) (12 * SCALE));
// aplly the inverse scale of what Libgdx will do at runtime
labelFont.setScale((float) (1.0 / SCALE));
// the resulting font scale is: 1.0 / SCALE * SCALE = 1
//Apply Linear filtering; best choice to keep everything looking sharp
labelFont.getRegion().getTexture().setFilter(TextureFilter.Linear, TextureFilter.Linear);
}
Bitmap fonts are textures and if you want to make smaller textures look smoother when you are resizing them to bigger sizes you need to make sure you use the right texture filter.
This blog post deals with such issues
With many things deprecated after the update, this is what's working for me:
public void regenerateFonts(OrthographicCamera cam, Game game) {
int size = 18;
if (cam != null && game != null) {
// camera and game are provided, recalculate sizes
float ratioX = cam.viewportWidth / game.getW();
float ratioY = cam.viewportHeight / game.getH();
System.out.println("Ratio: [" + ratioX + ":" + ratioY + "]");
size *= ratioY;
}
// font parameters for this size
FreeTypeFontParameter params = new FreeTypeFontParameter();
params.flip = true; // if your cam is flipped
params.characters = LETTERS; // your String containing all letters you need
params.size = size;
params.magFilter = TextureFilter.Linear; // used for resizing quality
params.minFilter = TextureFilter.Linear; // also
// Lato Light generator
FreeTypeFontGenerator generator = new FreeTypeFontGenerator(Gdx.files.internal("fonts/Lato-Light.ttf"));
// make the font
fontLatoLight = generator.generateFont(params);
generator.dispose(); // dispose to avoid memory leaks
}
And when you want to render it on the screen:
// text rendering
fontLatoLight.setColor(Color.WHITE); // set color here (has other overloads too)
fontLatoLight.draw(batch, "Hello World!", xCoord, yCoord);
My Solution for smooth text with Libgdx
I use BitmapFont and I generate 3 different size same fonts using Hiero tool
example Arial 16 , Arial 32, Arial 64
I put them in my assets file and use (load) only one of them depeding on the size of screen
if(Gdx.graphics.getWidth() < (480*3)/2)
{
textGametFont = BitmapFont(Gdx.files.internal(nameFont+16+".fnt"),
Gdx.files.internal(nameFont+16+".png"), false);
}else
{
if(Gdx.graphics.getWidth() < (3*920)/2)
{
textGametFont = new BitmapFont(Gdx.files.internal(nameFont+32+".fnt"),
Gdx.files.internal(nameFont+32+".png"), false);
}else
{
textGametFont = new BitmapFont(Gdx.files.internal(nameFont+64+".fnt"),
Gdx.files.internal(nameFont+64+".png"), false);
}
}
then I use this line of code to higher result quality of down and up Scaling
textGametFont.getRegion().getTexture().setFilter(TextureFilter.Linear, TextureFilter.Linear);
scale the image
to handle the size of the font for all type of resolution of device I use those two functions
public static float xTrans(float x)
{
return x*Gdx.graphics.width/(YourModel.SCREEN_WIDTH);
}
public static float yTrans(float y)
{
return y*Gdx.graphics.height/YourModel.SCREEN_Height;
}
the model screen resolution that i use is
SCREEN_WIDTH = 480
SCREEN_HEIGHT = 320
Set the scale to the font
textGametFont.setScale((xtrans(yourScale)+ ytrans(yourScale))/2f);
and finally draw your text
textGametFont.draw(batch, "WINNER !!", xTrans(250), yTrans(236));
Hope this was clear and helpful !!!
private BitmapFont font;
font = new BitmapFont();
font.scale((ppuX*0.02f));
font.draw(spb, "Score:", width/2-ppuX*2f, height-0.5f*ppuY);
Check out [this](http://www.badlogicgames.com/wordpress/?p=2300) blog post.
??? This just explains how to use the .scale() method which I'm stating is deprecated in the current release.
In scene2d, if you want apply antialiasing to all your labels, put this on constructor of your first screen:
skin.getFont("default-font").getRegion().getTexture().setFilter(Texture.TextureFilter.Linear, Texture.TextureFilter.Linear);
This is the first screen in my game:
...
public class MainMenuScreen implements Screen {
public MainMenuScreen() {
...
skin.getFont("default-font").getRegion().getTexture().setFilter(Texture.TextureFilter.Linear, Texture.TextureFilter.Linear);
}
}
Font name is in ui.json file, check for BitmapFont and Label$LabelStyle section:
"com.badlogic.gdx.graphics.g2d.BitmapFont": {
"default-font": {
"file": "default.fnt"
}
},
"com.badlogic.gdx.scenes.scene2d.ui.Label$LabelStyle": {
"default": {
"font": "default-font",
"fontColor": "white",
}
},