Moved texture examples to Topics

java/examples/Topics/Textures/TextureCube/TextureCube.pde

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+/**
+ * TexturedCube
+ * by Dave Bollinger.
+ * 
+ * Drag mouse to rotate cube. Demonstrates use of u/v coords in 
+ * vertex() and effect on texture(). The textures get distorted using
+ * the P3D renderer as you can see, but they look great using OPENGL.
+*/
+
+
+PImage tex;
+float rotx = PI/4;
+float roty = PI/4;
+
+void setup() 
+{
+  size(640, 360, P3D);
+  tex = loadImage("berlin-1.jpg");
+  textureMode(NORMALIZED);
+  fill(255);
+  stroke(color(44,48,32));
+}
+
+void draw() 
+{
+  background(0);
+  noStroke();
+  translate(width/2.0, height/2.0, -100);
+  rotateX(rotx);
+  rotateY(roty);
+  scale(90);
+  TexturedCube(tex);
+}
+
+void TexturedCube(PImage tex) {
+  beginShape(QUADS);
+  texture(tex);
+
+  // Given one texture and six faces, we can easily set up the uv coordinates
+  // such that four of the faces tile "perfectly" along either u or v, but the other
+  // two faces cannot be so aligned.  This code tiles "along" u, "around" the X/Z faces
+  // and fudges the Y faces - the Y faces are arbitrarily aligned such that a
+  // rotation along the X axis will put the "top" of either texture at the "top"
+  // of the screen, but is not otherwised aligned with the X/Z faces. (This
+  // just affects what type of symmetry is required if you need seamless
+  // tiling all the way around the cube)
+  
+  // +Z "front" face
+  vertex(-1, -1,  1, 0, 0);
+  vertex( 1, -1,  1, 1, 0);
+  vertex( 1,  1,  1, 1, 1);
+  vertex(-1,  1,  1, 0, 1);
+
+  // -Z "back" face
+  vertex( 1, -1, -1, 0, 0);
+  vertex(-1, -1, -1, 1, 0);
+  vertex(-1,  1, -1, 1, 1);
+  vertex( 1,  1, -1, 0, 1);
+
+  // +Y "bottom" face
+  vertex(-1,  1,  1, 0, 0);
+  vertex( 1,  1,  1, 1, 0);
+  vertex( 1,  1, -1, 1, 1);
+  vertex(-1,  1, -1, 0, 1);
+
+  // -Y "top" face
+  vertex(-1, -1, -1, 0, 0);
+  vertex( 1, -1, -1, 1, 0);
+  vertex( 1, -1,  1, 1, 1);
+  vertex(-1, -1,  1, 0, 1);
+
+  // +X "right" face
+  vertex( 1, -1,  1, 0, 0);
+  vertex( 1, -1, -1, 1, 0);
+  vertex( 1,  1, -1, 1, 1);
+  vertex( 1,  1,  1, 0, 1);
+
+  // -X "left" face
+  vertex(-1, -1, -1, 0, 0);
+  vertex(-1, -1,  1, 1, 0);
+  vertex(-1,  1,  1, 1, 1);
+  vertex(-1,  1, -1, 0, 1);
+
+  endShape();
+}
+
+void mouseDragged() {
+  float rate = 0.01;
+  rotx += (pmouseY-mouseY) * rate;
+  roty += (mouseX-pmouseX) * rate;
+}

java/examples/Topics/Textures/TextureCylinder/TextureCylinder.pde

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+/**
+ * Texture 3. 
+ * 
+ * Load an image and draw it onto a cylinder and a quad. 
+ */
+
+
+int tubeRes = 32;
+float[] tubeX = new float[tubeRes];
+float[] tubeY = new float[tubeRes];
+PImage img;
+
+void setup() {
+  size(640, 360, P3D);
+  img = loadImage("berlin-1.jpg");
+  float angle = 270.0 / tubeRes;
+  for (int i = 0; i < tubeRes; i++) {
+    tubeX[i] = cos(radians(i * angle));
+    tubeY[i] = sin(radians(i * angle));
+  }
+  noStroke();
+}
+
+void draw() {
+  background(0);
+  translate(width / 2, height / 2);
+  rotateX(map(mouseY, 0, height, -PI, PI));
+  rotateY(map(mouseX, 0, width, -PI, PI));
+  beginShape(QUAD_STRIP);
+  texture(img);
+  for (int i = 0; i < tubeRes; i++) {
+    float x = tubeX[i] * 100;
+    float z = tubeY[i] * 100;
+    float u = img.width / tubeRes * i;
+    vertex(x, -100, z, u, 0);
+    vertex(x, 100, z, u, img.height);
+  }
+  endShape();
+  beginShape(QUADS);
+  texture(img);
+  vertex(0, -100, 0, 0, 0);
+  vertex(100, -100, 0, 100, 0);
+  vertex(100, 100, 0, 100, 100);
+  vertex(0, 100, 0, 0, 100);
+  endShape();
+}

java/examples/Topics/Textures/TextureQuad/TextureQuad.pde

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+/**
+ * Texture 1. 
+ * 
+ * Load an image and draw it onto a quad. The texture() function sets
+ * the texture image. The vertex() function maps the image to the geometry.
+ */
+
+PImage img;
+
+void setup() {
+  size(640, 360, P3D);
+  img = loadImage("berlin-1.jpg");
+  noStroke();
+}
+
+void draw() {
+  background(0);
+  translate(width / 2, height / 2);
+  rotateY(map(mouseX, 0, width, -PI, PI));
+  rotateZ(PI/6);
+  beginShape();
+  texture(img);
+  vertex(-100, -100, 0, 0, 0);
+  vertex(100, -100, 0, 400, 0);
+  vertex(100, 100, 0, 400, 400);
+  vertex(-100, 100, 0, 0, 400);
+  endShape();
+}

java/examples/Topics/Textures/TextureTriangle/TextureTriangle.pde

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+/**
+ * Texture 2. 
+ * 
+ * Using a rectangular image to map a texture onto a triangle.
+ */
+
+PImage img;
+
+void setup() {
+  size(640, 360, P3D);
+  img = loadImage("berlin-1.jpg");
+  noStroke();
+}
+
+void draw() {
+  background(0);
+  translate(width / 2, height / 2);
+  rotateY(map(mouseX, 0, width, -PI, PI));
+  beginShape();
+  texture(img);
+  vertex(-100, -100, 0, 0, 0);
+  vertex(100, -40, 0, 400, 120);
+  vertex(0, 100, 0, 200, 400);
+  endShape();
+}