Check-in [7c222a4184]
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Overview
Comment:moved globals to beginning of draw.html added some null checking to matrix_vector_lib.js fixed small bugs (zooming in to much messes up axis draw)
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 7c222a418440d4b512c4e1de9395f2f06410dc2a
User & Date: Derek on 2012-12-24 03:52:54
Other Links: manifest | tags
Context
2012-12-24
04:23
(no comment) check-in: 17fe78b11b user: Derek tags: trunk
03:52
moved globals to beginning of draw.html added some null checking to matrix_vector_lib.js fixed small bugs (zooming in to much messes up axis draw) check-in: 7c222a4184 user: Derek tags: trunk
2012-12-23
19:18
removed superfulous code and comments. updated TODOs check-in: 1bc6e97248 user: Derek tags: trunk
Changes

Modified draw.html from [d50a5e8508] to [97f687849d].

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<html>
<script src='matrix_vector_lib.js' ></script>

<script>


//  TODO control with zoom rotate or pan means that action is only applied to the camera not the selected points.


//  TODO clicking and dragging on a line allows you to place a point somewhere on that line.  Perhaps with the modifier key it would break up the existing line into line segments.

//  TODO when lines are deleted, readd the solo points to the solo_points list
//  

//  TODO z for undo shift + z for redo.


//

//  TODO drop down minimalist menu in top right of canvas.


//  drag to connect points


var canvas;
var origin = [0, 0, 0];
var frame_rate = 20;
var saveTimeout = 10*1000;



var no_rotate_area = 0.80;
            
            







            































































var key_state = {};
var key_state_augmentation_delay = 150; // the permissible time in milliseconds since the last key event to still allow the key state to augment instead of clearing.

function addKeyListener(keycode, func){
    if(!key_state[keycode]) key_state[keycode] = {};
    
    var key_obj = key_state[keycode];
    if(!key_obj.listeners) key_obj.listeners = [];
    





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<html>
<script src='matrix_vector_lib.js' ></script>

<script>

//  TODO rotate selected points
//  TODO control with zoom rotate or pan means that action is only applied to the camera not the selected points.


//  TODO clicking and dragging on a line allows you to place a point somewhere on that line.  Perhaps with the modifier key it would break up the existing line into line segments.

//  TODO when lines are deleted, readd the solo points to the solo_points list
//  

//  TODO z for undo shift + z for redo.
//
//  TODO 
//

//  TODO drop down minimalist menu in top right of canvas.


//  drag to connect points


var canvas;
var origin = [0, 0, 0];
var frame_rate = 20;
var saveTimeout = 10*1000;

var forward_axis_size = 0.1;
var vertical_axis_size = 0.05;      

            
            

// to prevent camera from rotating beyond straight vertical
var vertical_camera_rotation = 0;
var zoom_dist = 1;
var zoom_factor = 0.83;
var zoom_scale = 2.667;  // scalar zoom property.
var last_zoom_dist = 1;
            

// camera animation
var max_move_delta = 0.01;
var max_angle_delta = Math.PI;

var delta_horizontal_angle = 0;
var delta_vertical_angle = 0;
var delta_position = [0,0,0];


//  Use to rotate selected points about a vector line
var selection_rotation_vector = null;
var rotation_center = origin.slice(0);





var points = []; //global
var solo_points = {};
var lines = [];

var point_projections = [];
var line_midpoint_projections = [];

var highlight_object = null;
var mouse_dragging = false;
var last_mouse_down = null;
var mouse_loc = null;
var MIN_DRAG_DIST = 10;
var POINT_HIGHLIGHT_DIST = 10;
var LINE_HIGHLIGHT_DIST = 15;

var selected_points = [];
var selected_lines = [];

var msg = //"3D drawing tool\n\n" +
          "Select     Left Click\n" +
		  "Rotate     Right Click\n" +
		  "Move       wasd, qe\n" +
		  "Copy       Space\n" +
		  "Delete     x\n" +
		  "\n" +
		  "Click the red dot to create a point\n" +
	      "Spam a motion key to increase speed\n";		  
	
	


var view_transform =
    [[1, 0, 0],
     [0, 1, 0],
     [0, 0, 1]];
    







            

var key_state = {};
var key_state_augmentation_timeout = 150; // the permissible time in milliseconds since the last key event to still allow the key state to augment instead of clearing.

function addKeyListener(keycode, func){
    if(!key_state[keycode]) key_state[keycode] = {};
    
    var key_obj = key_state[keycode];
    if(!key_obj.listeners) key_obj.listeners = [];
    
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    var state = key_obj.state;
    if(state) return; //key is already pressed.
    
    state = 0;
    
    var latest = key_obj.latest;

    if(latest && time - latest < key_state_augmentation_delay)
        state = key_obj.state = key_obj.lastState + 1;
    else
        state = key_obj.state = 1;
        
    key_obj.latest = time;
    
    key_obj.lastState = state;







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    var state = key_obj.state;
    if(state) return; //key is already pressed.
    
    state = 0;
    
    var latest = key_obj.latest;

    if(latest && time - latest < key_state_augmentation_timeout)
        state = key_obj.state = key_obj.lastState + 1;
    else
        state = key_obj.state = 1;
        
    key_obj.latest = time;
    
    key_obj.lastState = state;
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    if(!positive) delta = -delta;
    
    var velocityChange = [0, 0, 0];
    velocityChange[direction] = delta;
    vector_add(delta_position, velocityChange, delta_position); }
    

//
//  This 
//
    
function leftPress(e, s, lasts){
    changeVelocity(0, false, s, lasts); }
    
function rightPress(e, s, lasts){
     changeVelocity(0, true, s, lasts); }
     







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    if(!positive) delta = -delta;
    
    var velocityChange = [0, 0, 0];
    velocityChange[direction] = delta;
    vector_add(delta_position, velocityChange, delta_position); }
    

	


    
function leftPress(e, s, lasts){
    changeVelocity(0, false, s, lasts); }
    
function rightPress(e, s, lasts){
     changeVelocity(0, true, s, lasts); }
     
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				if(minx < _x && _x < maxx
				 && miny < _y && _y < maxy){
				   selected_points.push(i); }}}                
        }});





// to prevent camera from rotating beyond straight vertical
var vertical_camera_rotation = 0;
var NAVIGATION_ZOOM_DIST = 0.01;
var zoom_dist = 1;
var zoom_factor = 0.83;
var zoom_scale = 2.667;  // scalar zoom property.
var last_zoom_dist = 1;


// camera animation
var max_move_delta = 0.01;
var max_angle_delta = Math.PI / 2;

var delta_horizontal_angle = 0;
var delta_vertical_angle = 0;
var delta_position = [0,0,0];





var points = []; //global
var solo_points = {};
var lines = [];

var point_projections = [];
var line_midpoint_projections = [];

var highlight_object = null;
var mouse_dragging = false;
var last_mouse_down = null;
var mouse_loc = null;
var MIN_DRAG_DIST = 10;
var POINT_HIGHLIGHT_DIST = 10;
var LINE_HIGHLIGHT_DIST = 15;

var selected_points = [];
var selected_lines = [];

var msg = "3D drawing tool";


var view_transform =
    [[1, 0, 0],
     [0, 1, 0],
     [0, 0, 1]];
    

    
//  camera functions

function rotateView(norm, theta, cameracentric){

    // camera centric uses the camera axes to perform the rotation instead of the space axes.   







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				if(minx < _x && _x < maxx
				 && miny < _y && _y < maxy){
				   selected_points.push(i); }}}                
        }});


// right click
addKeyListener(1002, function(e, s, lasts){
	if(s == 0){













		delta_horizontal_angle = 0;
		delta_vertical_angle = 0; }});



function writeMsg(canvas, msg){




	var lines = msg.split("\n");
	var ctx = canvas.getContext("2d");


	ctx.font = "9pt sans-serif"







	for(var i = 0; i < lines.length; ++i){


		ctx.fillText(lines[i], 5, 10 + 15 *  i); }}









    
//  camera functions

function rotateView(norm, theta, cameracentric){

    // camera centric uses the camera axes to perform the rotation instead of the space axes.   
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        var x1 = _pt1[0];
        var y1 = _pt1[1];
        
        ctx.moveTo(x0, y0);
        ctx.lineTo(x1, y1); }
    
    ctx.clearRect(0, 0, w, h);
    var hoffset = h * (1 - no_rotate_area)/ 2;
    var woffset = w * (1 - no_rotate_area)/ 2;
    
    ctx.fillStyle = "rgba(128, 128, 128, 0.05)";
    ctx.fillRect(0, 0, w, hoffset);
    ctx.fillRect(0, hoffset, woffset, h - 2 * hoffset);
    ctx.fillRect(w - woffset, hoffset, woffset, h - 2 * hoffset);
    ctx.fillRect(0, h - hoffset, w, hoffset);
    
    ctx.fillStyle = "rgb(0, 0, 128)";
    ctx.stroke();
    

    for(var k in solo_points){
       var pt = point_projections[k];
       if(pt) ctx.fillRect(pt[0] - 2, pt[1] - 2, 4, 4); }
        
    
    




    

















	ctx.fillStyle = "rgba(250, 0, 0, 0.9)";
	ctx.fillRect(w/2 - 2, h/2 - 2, 4, 4);
	

	for(var i = 0; i < selected_points.length; ++i){
		var pt;
		
		if(selected_points[i] == -1)
			pt = [w/2, h/2];
		else pt = point_projections[selected_points[i]];
		







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        var x1 = _pt1[0];
        var y1 = _pt1[1];
        
        ctx.moveTo(x0, y0);
        ctx.lineTo(x1, y1); }
    
    ctx.clearRect(0, 0, w, h);


    





    
	ctx.strokeStyle = "rgba(0, 0, 0, 0.9)";
    ctx.stroke();
    
	ctx.fillStyle = "rgba(0, 0, 0, 0.9)";
    for(var k in solo_points){
       var pt = point_projections[k];
       if(pt) ctx.fillRect(pt[0] - 2, pt[1] - 2, 4, 4); }
        
    
    
	// axis lines and dots
	ctx.beginPath();
    var faxis_pt = project(canvas, vector_add(origin, [0, 0, forward_axis_size, 0, 0]), view_transform, origin);
	var vaxis_pt = project(canvas, vector_add(origin, [0, -vertical_axis_size, 0]), view_transform, origin);
    
	ctx.fillStyle = "rgba(0,0,0,0.9)";
	
	if(faxis_pt){
		ctx.moveTo(w/2, h/2);
		ctx.lineTo(faxis_pt[0], faxis_pt[1]);
		ctx.fillRect(faxis_pt[0] - 2, faxis_pt[1] - 2, 4, 4); }
		
	if(vaxis_pt){
		ctx.moveTo(w/2, h/2);
		ctx.lineTo(vaxis_pt[0], vaxis_pt[1]);
		ctx.fillRect(vaxis_pt[0] - 2, vaxis_pt[1] - 2, 4, 4); }
		
	ctx.stroke();	
	
	

    // red center dot.
	ctx.fillStyle = "rgba(250, 0, 0, 0.9)";
	ctx.fillRect(w/2 - 2, h/2 - 2, 4, 4);
	
	
	for(var i = 0; i < selected_points.length; ++i){
		var pt;
		
		if(selected_points[i] == -1)
			pt = [w/2, h/2];
		else pt = point_projections[selected_points[i]];
		
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	else{
		document.body.style.cursor = "crosshair"; }
	
	if(mouse_dragging){
	
		if(selected_points.length && (!key_state[16] || !key_state[16].state)){  // if shift is held, we are selecting more points.
			if(mouse_loc){
				ctx.beginPath();
				for(var i = 0; i < selected_points.length; ++i){
					var pt = point_projections[selected_points[i]];
					if(pt){
						ctx.moveTo(mouse_loc[0], mouse_loc[1]);
						ctx.lineTo(pt[0], pt[1]); }}
				ctx.stroke(); }}
		
		else if(mouse_loc && last_mouse_down){  // select points inside square            



			var minx = Math.min(mouse_loc[0], last_mouse_down[0]);
			var maxx = Math.max(mouse_loc[0], last_mouse_down[0]);
			var miny = Math.min(mouse_loc[1], last_mouse_down[1]);
			var maxy = Math.max(mouse_loc[1], last_mouse_down[1]);
			ctx.beginPath();
			ctx.rect(minx, miny, maxx-minx, maxy-miny);
			ctx.stroke(); }
	}
    
    ctx.fillStyle = "rgb(0,0,0)";
    ctx.fillText(msg, 5, 20); }

    
    
window.onload = function(){

    // load localStorage saved state.
    if(localStorage.points && localStorage.lines){







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	else{
		document.body.style.cursor = "crosshair"; }
	
	if(mouse_dragging){
	
		if(selected_points.length && (!key_state[16] || !key_state[16].state)){  // if shift is held, we are selecting more points.
			if(mouse_loc && key_state[1000] && key_state[1000].state){
				ctx.beginPath();

				var pt = point_projections[selected_points[0]];
					if(pt){
						ctx.moveTo(mouse_loc[0], mouse_loc[1]);
					ctx.lineTo(pt[0], pt[1]); }
				ctx.stroke(); }}
		
		else if(mouse_loc && last_mouse_down){  
		
		
		    if(key_state[1000] && key_state[1000].state){     // select points inside square
			var minx = Math.min(mouse_loc[0], last_mouse_down[0]);
			var maxx = Math.max(mouse_loc[0], last_mouse_down[0]);
			var miny = Math.min(mouse_loc[1], last_mouse_down[1]);
			var maxy = Math.max(mouse_loc[1], last_mouse_down[1]);
			ctx.beginPath();
			ctx.rect(minx, miny, maxx-minx, maxy-miny);
				ctx.stroke(); }}
	}
    
    ctx.fillStyle = "rgb(0,0,0)";
	writeMsg(canvas, msg); }

    
    
window.onload = function(){

    // load localStorage saved state.
    if(localStorage.points && localStorage.lines){
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        canvas.width = window.innerWidth - 20;
        canvas.height = window.innerHeight - 20; }

    
    
    function getRotationAngle(x, size, max, center_size){

        if(!center_size) center_size = 0.25;  // the proportional size of the area in which no rotation is effected by the mouse movement
        if(!max) max = Math.PI/128;
        x -= size/2;
        
        //  center does nothing
        if(Math.abs(x) < size * center_size/2) x = 0;
        else if(x < 0) x += size * center_size/2;
        else           x -= size * center_size/2;
        
        return max * x / ((1 - center_size) * size/2); }







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        canvas.width = window.innerWidth - 20;
        canvas.height = window.innerHeight - 20; }

    
    
    function getRotationAngle(x, size, max, center_size){

        if(!center_size) center_size = 0.05;  // the proportional size of the area in which no rotation is effected by the mouse movement
        if(!max) max = Math.PI/128;

        
        //  center does nothing
        if(Math.abs(x) < size * center_size/2) x = 0;
        else if(x < 0) x += size * center_size/2;
        else           x -= size * center_size/2;
        
        return max * x / ((1 - center_size) * size/2); }
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            var dist2 = _x*_x + _y*_y;
            
            if(dist2 > MIN_DRAG_DIST * MIN_DRAG_DIST){
                mouse_dragging = true; }}
                

				

		delta_horizontal_angle = getRotationAngle(x, w, max_angle_delta/frame_rate, no_rotate_area);
		delta_vertical_angle = -getRotationAngle(y, h, max_angle_delta/frame_rate, no_rotate_area);

		
		var min_point_dist2 = LINE_HIGHLIGHT_DIST * LINE_HIGHLIGHT_DIST;
		highlight_object = null;
		
		var _x = canvas.width/2 - x;
		var _y = canvas.height/2 - y;
		var point_dist = _x*_x + _y*_y;







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            var dist2 = _x*_x + _y*_y;
            
            if(dist2 > MIN_DRAG_DIST * MIN_DRAG_DIST){
                mouse_dragging = true; }}
                

				
	    if(key_state[1002] && key_state[1002].state && last_mouse_down){
			delta_horizontal_angle = getRotationAngle(x - last_mouse_down[0], w, max_angle_delta/frame_rate, 0);
			delta_vertical_angle = -getRotationAngle(y - last_mouse_down[1], h, max_angle_delta/frame_rate, 0); }
			
		
		var min_point_dist2 = LINE_HIGHLIGHT_DIST * LINE_HIGHLIGHT_DIST;
		highlight_object = null;
		
		var _x = canvas.width/2 - x;
		var _y = canvas.height/2 - y;
		var point_dist = _x*_x + _y*_y;

Modified matrix_vector_lib.js from [8300025cc5] to [0be33777c1].

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//  matrix and vector functions.
//
//

function vector_add(a, b, result){
    if(!result) result = [];



    if(a.length > b.lemgth){
        var tmp = a;
        a = b; b = tmp; }

    for(var i = 0; i < a.length; ++i){
        result[i] = a[i] + b[i]; }

    for(var i = a.length; i < b.length; ++i){
        result[i] = b[i]; }

    return result; }

    
function vector_cpy(result, a){

    for(var i = 0; i < a.length; ++i){
        result[i] = a[i]; }
}



function vector_minus(a, b, result){
    if(!result) result = [];



    var lim = Math.max(a.length, b.length);
    
    for(var i = 0; i < lim; ++i){
		var aValue, bValue;
		if(i < a.length)
			aValue = a[i];








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//  matrix and vector functions.
//
//

function vector_add(a, b, result){
    if(!result) result = [];
	if(!a) throw "first argument to vector_add missing";
	if(!b) throw "second argument to vector_add missing";

    if(a.length > b.lemgth){
        var tmp = a;
        a = b; b = tmp; }

    for(var i = 0; i < a.length; ++i){
        result[i] = a[i] + b[i]; }

    for(var i = a.length; i < b.length; ++i){
        result[i] = b[i]; }

    return result; }

    
function vector_cpy(result, a){
	if(!a) throw "first argument to vector_cpy missing";
    for(var i = 0; i < a.length; ++i){
        result[i] = a[i]; }
}



function vector_minus(a, b, result){
    if(!result) result = [];
	if(!a) throw "first argument to vector_minus missing";
	if(!b) throw "second argument to vector_minus missing";

    var lim = Math.max(a.length, b.length);
    
    for(var i = 0; i < lim; ++i){
		var aValue, bValue;
		if(i < a.length)
			aValue = a[i];
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    return result; }
   


function vector_dot(a, b){
    var lim = Math.min(a.length, b.length);



    var result = 0;

    for(var i = 0; i < lim; ++i){
        result += a[i] * b[i]; }

    return result; }
    
    
function vector_norm(a){

    return Math.sqrt(vector_dot(a,a)); }

    
    
    
function vector_scale(a, s, result){



    if(!result) result = [];
    
    for(var i = 0; i < a.length; ++i){
        result[i] = s * a[i]; }

    return result; }



// returns true iff the zero tail padded vectors match
function vector_cmp(a, b){



    if(a.length > b.length){
         var tmp = a;
         a = b; b = tmp; }

    for(var i = 0; i < a.length; ++i){
        if(a[i] != b[i]) 
			return false; }

    for(var i = a.length; i < b.length; ++i){
        if(b[i] != 0) 
			return false; }
            
    return true; }
    
    
    
function midpoint(a, b, result){



    if(b.length > a.length){
        var tmp = a;
        a = b; b = tmp; }
        
    if(!result) result = new Array(b.length);
        







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    return result; }
   


function vector_dot(a, b){
    var lim = Math.min(a.length, b.length);
	if(!a) throw "first argument to vector_dot missing";
	if(!b) throw "second argument to vector_dot missing";
	
    var result = 0;

    for(var i = 0; i < lim; ++i){
        result += a[i] * b[i]; }

    return result; }
    
    
function vector_norm(a){
	if(!a) throw "argument to vector_norm missing";
    return Math.sqrt(vector_dot(a,a)); }

    
    
    
function vector_scale(a, s, result){
	if(!a) throw "first argument to vector_scale missing";
	if(s === undefined || s === null) throw "scalar argument to vector_scale missing";

    if(!result) result = [];
    
    for(var i = 0; i < a.length; ++i){
        result[i] = s * a[i]; }

    return result; }



// returns true iff the zero tail padded vectors match
function vector_cmp(a, b){
	if(!a) throw "first argument to vector_cmp missing";
	if(!b) throw "second argument to vector_cmp missing";

    if(a.length > b.length){
         var tmp = a;
         a = b; b = tmp; }

    for(var i = 0; i < a.length; ++i){
        if(a[i] != b[i]) 
			return false; }

    for(var i = a.length; i < b.length; ++i){
        if(b[i] != 0) 
			return false; }
            
    return true; }
    
    
    
function vector_midpoint(a, b, result){
	if(!a) throw "first argument to vector_midpoint missing";
	if(!b) throw "second argument to vector_midpoint missing";

    if(b.length > a.length){
        var tmp = a;
        a = b; b = tmp; }
        
    if(!result) result = new Array(b.length);
        
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}




//this function may not care, but the expected matrix format in this project is a list of column vectors.
function matrix_transpose(matrix){


    var result = [];
    var dim0 = matrix.length;
    if(!dim0) 
		return result;

    var dim1 = matrix[0].length;







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}




//this function may not care, but the expected matrix format in this project is a list of column vectors.
function matrix_transpose(matrix){
	if(!matrix) throw "argument to matrix_transpose missing";

    var result = [];
    var dim0 = matrix.length;
    if(!dim0) 
		return result;

    var dim1 = matrix[0].length;
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function matrix_mult(a, b){



    var result = [];
    var a = matrix_transpose(a);
    var dim0 = a.length;
    var dim1 = b.length;

    for(var i = 0; i < dim1; ++i){







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function matrix_mult(a, b){
	if(!a) throw "first argument to matrix_mult missing";
	if(!b) throw "second argument to matrix_mult missing";

    var result = [];
    var a = matrix_transpose(a);
    var dim0 = a.length;
    var dim1 = b.length;

    for(var i = 0; i < dim1; ++i){
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// finds the inverse of a 3 by 3 matrix, returns false if matrix has determinant zero.
//

function matrix33inv(m){


    // the matrix format is a list of column vectors.
    var a = m[0][0];
	var b = m[1][0];
	var c = m[2][0];
	var d = m[0][1];
	var e = m[1][1];







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// finds the inverse of a 3 by 3 matrix, returns false if matrix has determinant zero.
//

function matrix33inv(m){
    if(!m) throw "argument to matrix33inv missing";

    // the matrix format is a list of column vectors.
    var a = m[0][0];
	var b = m[1][0];
	var c = m[2][0];
	var d = m[0][1];
	var e = m[1][1];
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	var result = [[di*A, di*B, di*C],
		          [di*D, di*E, di*F],
		          [di*G, di*H, di*K]];

	return result;  }

    


function compute_gradient(func, point, error){



    if(!error) error = 0.00001;

    // find gradient
    var otherpoint = point.slice(0);
    var gradient = new Array(point.length);
    var pointvalue = func(point);







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	var result = [[di*A, di*B, di*C],
		          [di*D, di*E, di*F],
		          [di*G, di*H, di*K]];

	return result;  }

    
// does not check if function is differentiable.

function compute_gradient(func, point, error){
	if(!func) throw "function argument to compute_gradient missing";
	if(!point) throw "point argument to compute_gradient missing";

    if(!error) error = 0.00001;

    // find gradient
    var otherpoint = point.slice(0);
    var gradient = new Array(point.length);
    var pointvalue = func(point);
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//
// equation at:
// http://inside.mines.edu/~gmurray/ArbitraryAxisRotation/ArbitraryAxisRotation.html
// creates a rotation matrix about the given vector.
//
function vector_rotation(vector, s){



    var len = Math.sqrt(vector[0]*vector[0]
                        + vector[1]*vector[1]
                        + vector[2]*vector[2]);

    var u = vector[0]/len;
    var v = vector[1]/len;







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//
// equation at:
// http://inside.mines.edu/~gmurray/ArbitraryAxisRotation/ArbitraryAxisRotation.html
// creates a rotation matrix about the given vector.
//
function vector_rotation(vector, s){
	if(!vector) throw "vector argument to vector_rotation missing";
	if(!s) throw "angle argument to vector_rotation missing";

    var len = Math.sqrt(vector[0]*vector[0]
                        + vector[1]*vector[1]
                        + vector[2]*vector[2]);

    var u = vector[0]/len;
    var v = vector[1]/len;