test/nashorn/script/jfx/spread.js
changeset 47216 71c04702a3d5
parent 24778 2ff5d7041566
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/nashorn/script/jfx/spread.js	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,222 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * Testing JavaFX canvas run by Nashorn.
+ *
+ * @test/nocompare
+ * @run
+ * @fork
+ */
+ 
+TESTNAME = "spread";
+
+var WIDTH = 800;
+var HEIGHT = 600;
+var canvas = new Canvas(WIDTH, HEIGHT);
+var context = canvas.graphicsContext2D;
+
+/* "Spread" tech demo of canvas by Tom Theisen
+ *
+ * This will animate a sequence of branch structures in a canvas element.
+ * Each frame, a new direction is calculated, similar to the last frame.
+ */
+
+var start_width = 20;           // starting width of each branch
+var frame_time = 30;            // milliseconds per frame
+var straighten_factor = 0.95;   // value from 0 to 1, factor applied to direction_offset every frame
+var curviness = 0.2;            // amount of random direction change each frame
+
+var color_speed = 0.03;     // speed at which colors change when cycling is enabled
+var branch_shrink = 0.95;   // factor by which branches shrink every frame
+var min_width = 1;          // minimum WIDTH for branch, after which they are discontinued
+var branch_opacity = 0.4;   // opacity of lines drawn
+var branch_count = 3;       // branch count per tree
+var branch_bud_size = 0.5;  // ratio of original branch size at which branch will split
+var branch_bud_angle = 1;   // angle offset for split branch;
+
+var paper;                  // reference to graphics context
+var branches = Object();    // linked list of active branches
+var color_styles = [];      // pre-computed list of colors as styles. format: (r,g,b,a)    
+var direction_offset = 0;   // current direction offset in radians.  this is applied to all branches.
+var frame = 0;              // frame counter
+var timespent = 0;          // total time spent so far, used to calculate average frame render duration
+var frameratespan;          // html span element for updating performance number
+
+// preferences object, contains an attribute for each user setting
+var prefs = {
+    wrap: true,             // causes branches reaching edge of viewable area to appear on opposite side
+    fade: false,             // fade existing graphics on each frame
+    cycle: true,            // gradually change colors each frame
+    new_branch_frames: 20    // number of frames elapsed between each auto-generated tree
+};
+
+// create tree at the specified position with number of branches
+function create_tree(branches, start_width, position, branch_count) {
+    var angle_offset = Math.PI * 2 / branch_count;
+    for (var i = 0; i < branch_count; ++i) {
+        branch_add(branches, new Branch(position, angle_offset * i, start_width));
+    }
+}
+
+// add branch to collection
+function branch_add(branches, branch) {
+    branch.next = branches.next;
+    branches.next = branch;
+}
+
+// get the coordinates for the position of a new tree
+// use the center of the canvas
+function get_new_tree_center(width, height) {
+    return {
+        x: 0.5 * width, 
+        y: 0.5 * height 
+    };
+}
+
+// Branch constructor
+// position has x and y properties
+// direction is in radians
+function Branch(position, direction, width) {
+    this.x = position.x;
+    this.y = position.y;
+    this.width = width;
+    this.original_width = width;
+    this.direction = direction;
+}
+
+// update position, direction and width of a particular branch
+function branch_update(branches, branch, paper) {
+    paper.beginPath();
+    paper.lineWidth = branch.width;
+    paper.moveTo(branch.x, branch.y);
+    
+    branch.width *= branch_shrink;
+    branch.direction += direction_offset;
+    branch.x += Math.cos(branch.direction) * branch.width;
+    branch.y += Math.sin(branch.direction) * branch.width;
+    
+    paper.lineTo(branch.x, branch.y);
+    paper.stroke();
+    
+    if (prefs.wrap) wrap_branch(branch, WIDTH, HEIGHT);
+
+    if (branch.width < branch.original_width * branch_bud_size) {
+        branch.original_width *= branch_bud_size;
+        branch_add(branches, new Branch(branch, branch.direction + 1, branch.original_width));
+    }
+}
+
+function draw_frame() {
+    if (prefs.fade) {
+        paper.fillRect(0, 0, WIDTH, HEIGHT);
+    }
+
+    if (prefs.cycle) {
+        paper.setStroke(Paint.valueOf(color_styles[frame % color_styles.length]));
+    }
+
+    if (frame++ % prefs.new_branch_frames == 0) {
+        create_tree(branches, start_width, get_new_tree_center(WIDTH, HEIGHT), branch_count);
+    }
+    
+    direction_offset += (0.35 + (frame % 200) * 0.0015) * curviness - curviness / 2;
+    direction_offset *= straighten_factor;
+    
+    var branch = branches;
+    var prev_branch = branches;
+    while (branch = branch.next) {
+        branch_update(branches, branch, paper);
+        
+        if (branch.width < min_width) {
+            // remove branch from list
+            prev_branch.next = branch.next;
+        }
+        
+        prev_branch = branch;
+    }
+}
+
+// constrain branch position to visible area by "wrapping" from edge to edge
+function wrap_branch(branch, WIDTH, HEIGHT) {
+    branch.x = positive_mod(branch.x, WIDTH);
+    branch.y = positive_mod(branch.y, HEIGHT);
+}
+
+// for a < 0, b > 0, javascript returns a negative number for a % b
+// this is a variant of the % operator that adds b to the result in this case
+function positive_mod(a, b) {
+    // ECMA 262 11.5.3: Applying the % Operator 
+    // remainder operator does not convert operands to integers,
+    // although negative results are possible
+
+    return ((a % b) + b) % b;
+}
+
+// pre-compute color styles that will be used for color cycling
+function populate_colors(color_speed, color_styles, branch_opacity) {
+    // used in calculation of RGB values
+    var two_thirds_pi = Math.PI * 2 / 3;
+    var four_thirds_pi = Math.PI * 4 / 3;
+    var two_pi = Math.PI * 2;
+
+    // hue does represent hue, but not in the conventional HSL scheme
+    for(var hue = 0; hue < two_pi; hue += color_speed) {
+        var r = Math.floor(Math.sin(hue) * 128 + 128);
+        var g = Math.floor(Math.sin(hue + two_thirds_pi) * 128 + 128);
+        var b = Math.floor(Math.sin(hue + four_thirds_pi) * 128 + 128);
+        color = "rgba(" + [r, g, b, branch_opacity].join() + ")";
+
+        color_styles.push(color);
+    }
+}
+
+// apply initial settings to canvas object
+function setup_canvas() {
+    paper = canvas.graphicsContext2D;
+    paper.setFill(Paint.valueOf('rgb(0, 0, 0)'));
+    paper.fillRect(0, 0, WIDTH, HEIGHT);
+    paper.setFill(Paint.valueOf("rgba(0, 0, 0, 0.005)"));
+    paper.setStroke(Paint.valueOf("rgba(128, 128, 64, " + String(branch_opacity) + ")"));
+}
+
+populate_colors(color_speed, color_styles, branch_opacity);
+setup_canvas();
+
+var stack = new StackPane();
+var pane = new BorderPane();
+pane.setCenter(canvas);
+stack.getChildren().add(pane);
+$STAGE.scene = new Scene(stack);
+var timer = new AnimationTimerExtend() {
+    handle: function handle(now) {
+        if (frame < 200) {
+            draw_frame();
+        } else {
+            checkImageAndExit();
+            timer.stop();
+        }
+    }
+};
+timer.start();
+