void buildH(GWindow& gw,
int lengthCnt,
int requiredOrder,
GPoint& centerPt,
double length,
double angle){
if(requiredOrder >= 0){
lengthCnt++;
int koef = lengthCnt%2;
if(koef){ length = length / 2;
}else{requiredOrder--;}
GPoint pt1 = gw.drawPolarLine(centerPt, length, angle);
GPoint pt2 = gw.drawPolarLine(centerPt, length, (180 + angle));
/* Left brunch */
buildH(gw,
lengthCnt,
requiredOrder,
pt1,
(length),
(angle + 90));
/* Right brunch */
buildH(gw,
lengthCnt,
requiredOrder,
pt2,
(length),
(angle - 90));
}
}
GPoint drawFractalTree(GWindow & gw, GPoint pt, double size, double theta, int order){
GPoint ptMid = gw.drawPolarLine (pt, size, theta);
if(order == 0){
return gw.drawPolarLine (pt, size, theta);
}else{
double angle = 20;
//double angle = randomReal (10,60); // use it for more fun
drawFractalTree (gw, ptMid, size * 0.7, theta - angle, order - 1);
drawFractalTree (gw, ptMid, size * 0.7, theta + angle, order - 1);
return drawFractalTree (gw, pt, size, theta, order - 1 );
}
}
//builds two lines from each of two gotten vertex and calls itself recursively until the depth of recursion becomes zero
void drawPythagoreanTree(GWindow &gw, GPoint endPoint1, GPoint endPoint2, double input_length, double theta, int recursion_depth){
double theta_one = theta - THETA;
double theta_two = theta + THETA;
double length = input_length * cos(THETA_RADIAN);
GPoint branch1_1 = gw.drawPolarLine(endPoint1, length*2, theta_one);
GPoint branch1_2 = gw.drawPolarLine(endPoint2, length, theta_one);
gw.setColor("YELLOW");
gw.drawLine(branch1_1, branch1_2);
GPoint branch2_1 = gw.drawPolarLine(endPoint1, length, theta_two);
GPoint branch2_2 = gw.drawPolarLine(endPoint2, length*2, theta_two);
gw.setColor("GREEN");
gw.drawLine(branch2_1, branch2_2);
recursion_depth--;
if(recursion_depth == 0){
return;
}
drawPythagoreanTree(gw, branch1_1, branch1_2, length, theta_one, recursion_depth);
drawPythagoreanTree(gw, branch2_1, branch2_2, length, theta_two, recursion_depth);
}
static void drawTree(GWindow& window, int order, GPoint startPoint, int startAngle, double len) {
if (order == 0)
{
window.setColor(kLeafColor);
window.drawPolarLine(startPoint, len, startAngle);
}
else
{
double nextLen = len * kShrinkFactor;
window.setColor(order < 2 ? kLeafColor : kTrunkColor);
GPoint trunkEnd = window.drawPolarLine(startPoint, len, startAngle);
for (int i = 0; i < 7; ++i)
{
if (randomReal(0.0, 1.0) < 0.8)
{
int angle = startAngle - 45 + i * kBranchAngleSeparation;
drawTree(window, order - 1, trunkEnd, angle, nextLen);
}
}
}
}
static GPoint drawSierpinskiTriangle (int edgeLength, int fractalOrder, double cx, double cy, GWindow &window){
// BASE CASE: ORDER = 0
if (fractalOrder==0){
int outlineTriangleHeight = sqrt(edgeLength*edgeLength - (edgeLength/2)*(edgeLength/2));
GPoint pt0 (cx - edgeLength/2, cy + outlineTriangleHeight/2);
pt0 = window.drawPolarLine(pt0, edgeLength, 0);
pt0 = window.drawPolarLine(pt0, edgeLength, +120);
pt0 = window.drawPolarLine(pt0, edgeLength, -120);
return pt0;
}
// RECURSIVE STEP
edgeLength = edgeLength/2;
int triangleHeight = sqrt(edgeLength*edgeLength - (edgeLength/2)*(edgeLength/2));
// Three bottom left points for three inner triangles
GPoint pt1 (cx - edgeLength, cy + triangleHeight);
GPoint pt2 (cx, cy + triangleHeight);
GPoint pt3 (cx - edgeLength/2, cy);
// Draw bottom left triangle
pt1 = window.drawPolarLine(pt1, edgeLength, 0);
pt1 = window.drawPolarLine(pt1, edgeLength, +120);
pt1 = window.drawPolarLine(pt1, edgeLength, -120);
int bottomLeftCentreXDimension = cx-edgeLength/2;
int bottomLeftCentreYDimension = cy+triangleHeight/2;
drawSierpinskiTriangle (edgeLength, fractalOrder-1, bottomLeftCentreXDimension, bottomLeftCentreYDimension, window);
// Draw bottom right triangle
pt2 = window.drawPolarLine(pt2, edgeLength, 0);
pt2 = window.drawPolarLine(pt2, edgeLength, +120);
pt2 = window.drawPolarLine(pt2, edgeLength, -120);
int bottomRightCentreXDimension = cx+edgeLength/2;
int bottomRightCentreYDimension = cy+triangleHeight/2;
drawSierpinskiTriangle (edgeLength, fractalOrder-1, bottomRightCentreXDimension, bottomRightCentreYDimension, window);
// Draw top triangle
pt3 = window.drawPolarLine(pt3, edgeLength, 0);
pt3 = window.drawPolarLine(pt3, edgeLength, +120);
pt3 = window.drawPolarLine(pt3, edgeLength, -120);
int topXDimension = cx;
int topYDimention = cy - triangleHeight/2;
drawSierpinskiTriangle (edgeLength, fractalOrder-1, topXDimension, topYDimention, window);
return pt1;
}