From: Shaheen Gandhi Date: Sun, 18 Aug 2013 21:47:46 +0000 (-0700) Subject: [Helix] Cleanups X-Git-Url: https://git.piment-noir.org/?a=commitdiff_plain;h=ee1f21c7b393e36fe80d72398206cd03df665052;p=SugarCubes.git [Helix] Cleanups --- diff --git a/ShaheenGandhi.pde b/ShaheenGandhi.pde index 740883d..c25badd 100644 --- a/ShaheenGandhi.pde +++ b/ShaheenGandhi.pde @@ -7,42 +7,40 @@ class HelixPattern extends SCPattern { private class Line { private final PVector origin; private final PVector vector; - + Line(PVector pt, PVector v) { origin = pt; vector = v.get(); vector.normalize(); } - + PVector getPoint() { return origin; } - + PVector getVector() { return vector; } - - PVector getPointAt(float t) { - PVector pt = PVector.mult(vector, t); - pt.add(origin); - return pt; + + PVector getPointAt(final float t) { + return PVector.add(origin, PVector.mult(vector, t)); } - - boolean isColinear(PVector pt) { - PVector projected = projected(pt); + + boolean isColinear(final PVector pt) { + PVector projected = projectPoint(pt); return projected.x==pt.x && projected.y==pt.y && projected.z==pt.z; } - - float getTValue(PVector pt) { + + float getTValue(final PVector pt) { PVector subtraction = PVector.sub(pt, origin); return subtraction.dot(vector); - } - - PVector projected(PVector pt) { + } + + PVector projectPoint(final PVector pt) { return getPointAt(getTValue(pt)); } - - PVector rotatePoint(PVector pt, float rads) { + + PVector rotatePoint(final PVector pt, final float rads) { Vec3D axisVec3D = new Vec3D(vector.x, vector.y, vector.z); Matrix4x4 mat = new Matrix4x4(); mat.rotateAroundAxis(axisVec3D, rads); @@ -54,10 +52,10 @@ class HelixPattern extends SCPattern { private class Helix { private final Line axis; - private final float period; - private final float rotationPeriod; - private final float radius; - private final float girth; + private final float period; // period of coil + private final float rotationPeriod; // animation period + private final float radius; // radius of coil + private final float girth; // girth of coil private final PVector referencePoint; private float phase; private PVector phaseNormal; @@ -81,47 +79,48 @@ class HelixPattern extends SCPattern { } this.referencePoint = pt; - this.phase = phase; - setPhaseNormalFromPhase(); - } - - private void setPhaseNormalFromPhase() { - phaseNormal = axis.getVector().cross(axis.rotatePoint(referencePoint, phase)); + // The normal is calculated by the cross product of the axis + // and a random point that is not colinear with it. + phaseNormal = axis.getVector().cross(referencePoint); phaseNormal.normalize(); phaseNormal.mult(radius); } - + private void setPhase(float phase) { this.phase = phase; setPhaseNormalFromPhase(); } - + + Line getAxis() { + return axis; + } + void step(int deltaMs) { - setPhase(phase + (deltaMs / rotationPeriod) * TWO_PI); + // Rotate + if (rotationPeriod != 0) { + setPhase(phase + (deltaMs / rotationPeriod) * TWO_PI); + } } - + PVector pointOnToroidalAxis(float t) { PVector p = axis.getPointAt(t); PVector middle = PVector.add(p, phaseNormal); return axis.rotatePoint(middle, (t / period) * TWO_PI); } - - color colorOfPoint(PVector p) { - // Calculate the projection of this point to the axis. - PVector projectedPoint = axis.projected(p); - + + color colorOfPoint(final PVector p) { // Find the appropriate point for the current rotation // of the helix. float t = axis.getTValue(projectedPoint); PVector toroidPoint = pointOnToroidalAxis(t); - + // The rotated point represents the middle of the girth of // the helix. Figure out if the current point is inside that // region. float d = PVector.dist(p, toroidPoint); boolean inToroid = d < girth; - + // Soften edges by fading brightness float b = constrain(100*(1 - ((d-.5*girth)/(girth*.5))), 0, 100); return color((lx.getBaseHuef() + (360*(phase / TWO_PI)))%360, (inToroid ? 80 : 0), b); @@ -130,16 +129,16 @@ class HelixPattern extends SCPattern { private final Helix h1; private final Helix h2; - + private final BasicParameter helix1On = new BasicParameter("H1ON", 1); private final BasicParameter helix2On = new BasicParameter("H2ON", 1); - + public HelixPattern(GLucose glucose) { super(glucose); - + addParameter(helix1On); addParameter(helix2On); - + h1 = new Helix( new Line(new PVector(100, 50, 70), new PVector(1,0,0)), 700, // period @@ -160,28 +159,28 @@ class HelixPattern extends SCPattern { // parameterized t value. select base pairs and // associated colors. lerp between colors for each // base pair to produce a DNA effect. - + } - + void run(int deltaMs) { boolean h1on = helix1On.getValue() > 0.5; boolean h2on = helix2On.getValue() > 0.5; - + h1.step(deltaMs); h2.step(deltaMs); - + for (Point p : model.points) { color h1c = color(0,0,0); color h2c = color(0,0,0); - + if (h1on) { h1c = h1.colorOfPoint(new PVector(p.x,p.y,p.z)); } - + if (h2on) { h2c = h2.colorOfPoint(new PVector(p.x,p.y,p.z)); } - + // The helices are positioned to not overlap. If that changes, // a better blending formula is probably needed. colors[p.index] = blendColor(h1c, h2c, ADD);