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Q-W1 pt2: core/shell/app relocation + sub-namespaces; one concrete ui::Rect (LTRB fork retired); slot_map split from bank_book; BankIndex→BankModel; 59/59 green

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Daniel Harvey
2026-07-28 20:48:56 -04:00
parent 67a41728f3
commit 847936f813
222 changed files with 2247 additions and 2079 deletions
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src/core/instrument/engine/velocity_curve.cpp
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// velocity_curve.cpp — see velocity_curve.h. Pure eval + editing/clamp/inverse map; no host types.
#include "core/instrument/engine/velocity_curve.h"
#include <algorithm> // std::max, std::min, std::abs, std::stable_sort
#include <cmath> // std::fabs
#include <utility> // std::move
namespace reasampler::instrument::engine {
namespace {
double clampVelocity(double v) { return std::clamp(v, kVelMin, kVelMax); }
double clampAmp(double a) { return std::clamp(a, kAmpMin, kAmpMax); }
// Pixel<->box maps (mirror of envelope_edit's timeToX/levelToY). X spans the width for [0,127]; Y
// spans (height-1) rows for amp [0,1] with amp 1 at the TOP (y increases downward).
double velPerPixel(const VelocityCurve::Box& box) {
const int w = std::max(0, box.width);
if (w <= 0) return 0.0;
return (kVelMax - kVelMin) / static_cast<double>(w);
}
double ampPerPixel(const VelocityCurve::Box& box) {
const int h = std::max(0, box.height);
if (h <= 1) return 0.0;
return (kAmpMax - kAmpMin) / static_cast<double>(h - 1);
}
int velToX(const VelocityCurve::Box& box, double velocity) {
const int w = std::max(0, box.width);
if (w <= 0) return box.left;
const double frac = (clampVelocity(velocity) - kVelMin) / (kVelMax - kVelMin);
return box.left + static_cast<int>(frac * static_cast<double>(w) + 0.5);
}
int ampToY(const VelocityCurve::Box& box, double amp) {
const int h = std::max(0, box.height);
if (h <= 1) return box.top;
// amp 1 at top (box.top), amp 0 at bottom (box.top + h - 1).
const double frac = (clampAmp(amp) - kAmpMin) / (kAmpMax - kAmpMin);
return box.top + static_cast<int>((1.0 - frac) * static_cast<double>(h - 1) + 0.5);
}
} // namespace
VelocityCurve VelocityCurve::flat() {
VelocityCurve c;
c.points_ = {{kVelMin, kAmpMax}, {kVelMax, kAmpMax}}; // y = 1 everywhere (R10-F1 Option A)
return c;
}
VelocityCurve VelocityCurve::linear() {
VelocityCurve c;
c.points_ = {{kVelMin, kAmpMin}, {kVelMax, kAmpMax}}; // y = velocity/127
return c;
}
VelocityCurve VelocityCurve::fromPoints(std::vector<VelocityPoint> pts) {
// Box-clamp every point, then stable-sort by velocity (X-order; stable so coincident-X points
// keep their wire order). A stable sort keeps the eval well-defined for duplicate-X knots.
for (VelocityPoint& p : pts) {
p.velocity = clampVelocity(p.velocity);
p.amp = clampAmp(p.amp);
}
std::stable_sort(pts.begin(), pts.end(),
[](const VelocityPoint& a, const VelocityPoint& b) {
return a.velocity < b.velocity;
});
// Fewer than 2 usable points -> can't span [0,127] as a function; fall back to the flat default.
if (pts.size() < 2) return flat();
// Force endpoints present at velocity 0 and 127 (they must exist for eval to be total).
if (pts.front().velocity > kVelMin) {
pts.insert(pts.begin(), VelocityPoint{kVelMin, pts.front().amp});
} else {
pts.front().velocity = kVelMin; // snap a near-0 first point exactly onto the endpoint
}
if (pts.back().velocity < kVelMax) {
pts.push_back(VelocityPoint{kVelMax, pts.back().amp});
} else {
pts.back().velocity = kVelMax; // snap a near-127 last point exactly onto the endpoint
}
VelocityCurve c;
c.points_ = std::move(pts);
return c;
}
namespace {
// Fritsch–Carlson monotone-cubic tangent for one interior knot i, given the secant slopes of the
// two adjacent segments (dPrev = secant into knot i, dNext = secant out of knot i). Returns the
// limited tangent that keeps the cubic Hermite piece monotone and inside the data range.
//
// The rule: a tangent whose adjacent secants have opposite signs (or either is flat) is a local
// extremum — pin the tangent to 0 so the curve does not overshoot past the knot. Otherwise use the
// weighted-harmonic-mean tangent (Fritsch–Carlson eq. 4), which for COLLINEAR knots (dPrev==dNext)
// reduces to that common secant — so collinear control points reproduce the straight line to within
// floating-point rounding (~1e-15), preserving the Option-B / null-response contract for linear().
double fritschCarlsonTangent(double dPrev, double dNext, double spanPrev, double spanNext) {
if (dPrev * dNext <= 0.0) return 0.0; // sign change or a flat neighbour -> local extremum
// Weighted harmonic mean of the two secants (weights = the two segment widths). Collinear case:
// dPrev==dNext==d makes this (w1+w2)*d / ((w1+w2)/... ) collapse to d exactly.
const double w1 = 2.0 * spanNext + spanPrev;
const double w2 = spanNext + 2.0 * spanPrev;
return (w1 + w2) / (w1 / dPrev + w2 / dNext);
}
} // namespace
double VelocityCurve::eval(double velocity) const {
if (points_.empty()) return kAmpMax; // degenerate (shouldn't occur) -> flat unity
if (points_.size() == 1) return clampAmp(points_[0].amp); // 1-point -> that point's amp
const double v = clampVelocity(velocity);
// At or before the first point / at or after the last, read the endpoint amp (the endpoints are
// at 0 and 127, so this only fires exactly at the ends for an in-range velocity).
if (v <= points_.front().velocity) return clampAmp(points_.front().amp);
if (v >= points_.back().velocity) return clampAmp(points_.back().amp);
// Find the segment [points_[i], points_[i+1]] containing v (X-ordered, so a linear scan).
for (std::size_t i = 0; i + 1 < points_.size(); ++i) {
const VelocityPoint& a = points_[i];
const VelocityPoint& b = points_[i + 1];
if (v >= a.velocity && v <= b.velocity) {
const double span = b.velocity - a.velocity;
// Coincident-X neighbours (a step): jump straight to the later point's amp — the segment
// has zero width so there is no interior to blend.
if (span <= 0.0) return clampAmp(b.amp);
// --- Monotone cubic Hermite (Fritsch–Carlson) interpolation on segment [a,b] ---------
// Curved (spline) response, not straight lines. The interpolant provably stays within
// [a.amp, b.amp] between the two knots (no bulge below 0 / above 1), and for collinear
// control points its tangents reduce to the secant slope — so it reproduces the straight
// line to within floating-point rounding (~1e-15), preserving linear()'s null-response
// contract (y = velocity/127 to ~1e-15; the test tolerance of 1e-12 is appropriate).
const double d = (b.amp - a.amp) / span; // secant of THIS segment
// Tangent at a: 0 if a is the first knot (endpoint), else the FC-limited tangent using
// the previous segment's secant. Same for the tangent at b (0 at the last knot).
double mA = d;
if (i > 0) {
const VelocityPoint& prev = points_[i - 1];
const double spanPrev = a.velocity - prev.velocity;
if (spanPrev > 0.0) {
const double dPrev = (a.amp - prev.amp) / spanPrev;
mA = fritschCarlsonTangent(dPrev, d, spanPrev, span);
} else {
mA = 0.0; // coincident-X predecessor (a step at a) -> flat tangent
}
}
double mB = d;
if (i + 2 < points_.size()) {
const VelocityPoint& next = points_[i + 2];
const double spanNext = next.velocity - b.velocity;
if (spanNext > 0.0) {
const double dNext = (next.amp - b.amp) / spanNext;
mB = fritschCarlsonTangent(d, dNext, span, spanNext);
} else {
mB = 0.0; // coincident-X successor (a step at b) -> flat tangent
}
}
// Cubic Hermite basis on the normalized position t across [a,b]. For collinear knots
// mA==mB==d, so h00*a + (h10*span)*d + h01*b + (h11*span)*d collapses to the straight
// line to within floating-point rounding (~1e-15).
const double t = (v - a.velocity) / span;
const double t2 = t * t;
const double t3 = t2 * t;
const double h00 = 2.0 * t3 - 3.0 * t2 + 1.0;
const double h10 = t3 - 2.0 * t2 + t;
const double h01 = -2.0 * t3 + 3.0 * t2;
const double h11 = t3 - t2;
const double y = h00 * a.amp + h10 * span * mA + h01 * b.amp + h11 * span * mB;
return clampAmp(y);
}
}
return clampAmp(points_.back().amp); // unreachable (v is between the endpoints)
}
std::size_t VelocityCurve::addPoint(double velocity, double amp) {
const VelocityPoint p{clampVelocity(velocity), clampAmp(amp)};
// Insert keeping X-order: first index whose velocity is STRICTLY greater than the new one, so a
// duplicate-X point lands immediately after the existing one (a later move can separate them).
std::size_t i = 0;
while (i < points_.size() && points_[i].velocity <= p.velocity) ++i;
points_.insert(points_.begin() + static_cast<std::ptrdiff_t>(i), p);
return i;
}
VelocityPoint VelocityCurve::movePoint(std::size_t index, double velocity, double amp) {
if (index >= points_.size()) return VelocityPoint{}; // no-op (out of range)
const bool isFirst = (index == 0);
const bool isLast = (index + 1 == points_.size());
double newAmp = clampAmp(amp);
double newVel;
if (isFirst) {
newVel = kVelMin; // endpoint pinned in X at 0 — only amp moves
} else if (isLast) {
newVel = kVelMax; // endpoint pinned in X at 127 — only amp moves
} else {
// Interior point: clamp X strictly within its immediate neighbours so it can't cross them.
const double lo = points_[index - 1].velocity;
const double hi = points_[index + 1].velocity;
newVel = std::clamp(clampVelocity(velocity), lo, hi);
}
points_[index] = VelocityPoint{newVel, newAmp};
return points_[index];
}
bool VelocityCurve::deletePoint(std::size_t index) {
if (index >= points_.size()) return false;
if (index == 0 || index + 1 == points_.size()) return false; // endpoints are not deletable
points_.erase(points_.begin() + static_cast<std::ptrdiff_t>(index));
return true;
}
VelocityCurve::CurvePixel VelocityCurve::pixelFromPoint(const Box& box, const VelocityPoint& p) {
return CurvePixel{velToX(box, p.velocity), ampToY(box, p.amp)};
}
VelocityPoint VelocityCurve::pointFromPixel(const Box& box, int x, int y) {
// The exact inverse of velToX/ampToY (within the one-pixel rounding quantum). Degenerate
// dimensions collapse the same way the forward map does: velToX pins to box.left (velocity 0),
// ampToY pins to box.top (amp 1).
VelocityPoint p;
const int w = std::max(0, box.width);
const int h = std::max(0, box.height);
p.velocity = (w <= 0)
? kVelMin
: clampVelocity(kVelMin + static_cast<double>(x - box.left) / static_cast<double>(w) *
(kVelMax - kVelMin));
p.amp = (h <= 1)
? kAmpMax
: clampAmp(kAmpMax - static_cast<double>(y - box.top) / static_cast<double>(h - 1) *
(kAmpMax - kAmpMin));
return p;
}
int VelocityCurve::pointAtPixel(const Box& box, int x, int y) const {
for (std::size_t i = 0; i < points_.size(); ++i) {
const int px = velToX(box, points_[i].velocity);
const int py = ampToY(box, points_[i].amp);
if (std::abs(x - px) <= kCurveNodeGrabRadius && std::abs(y - py) <= kCurveNodeGrabRadius) {
return static_cast<int>(i);
}
}
return -1;
}
VelocityCurve VelocityCurve::resolvePointDrag(const VelocityCurve& grabCurve, std::size_t index,
const Box& box, int dxPixels, int dyPixels) {
VelocityCurve out = grabCurve;
if (index >= out.points_.size()) return out; // out of range -> no motion
const double velPerPx = velPerPixel(box);
const double ampPerPx = ampPerPixel(box);
if (velPerPx <= 0.0 || ampPerPx <= 0.0) return out; // degenerate box -> no motion
const VelocityPoint& grab = grabCurve.points_[index];
const double newVel = grab.velocity + static_cast<double>(dxPixels) * velPerPx;
// Y increases downward but amp increases upward, so a downward drag (positive dy) LOWERS amp.
const double newAmp = grab.amp - static_cast<double>(dyPixels) * ampPerPx;
out.movePoint(index, newVel, newAmp); // applies box + neighbour-X + endpoint-pin clamps
return out;
}
bool VelocityCurve::equals(const VelocityCurve& other, double eps) const {
if (points_.size() != other.points_.size()) return false;
for (std::size_t i = 0; i < points_.size(); ++i) {
if (std::fabs(points_[i].velocity - other.points_[i].velocity) > eps) return false;
if (std::fabs(points_[i].amp - other.points_[i].amp) > eps) return false;
}
return true;
}
} // namespace reasampler::instrument::engine