diff options
Diffstat (limited to 'src/3rdparty/harfbuzz-ng/src/hb-subset-instancer-solver.cc')
| -rw-r--r-- | src/3rdparty/harfbuzz-ng/src/hb-subset-instancer-solver.cc | 292 |
1 files changed, 131 insertions, 161 deletions
diff --git a/src/3rdparty/harfbuzz-ng/src/hb-subset-instancer-solver.cc b/src/3rdparty/harfbuzz-ng/src/hb-subset-instancer-solver.cc index 5c0f43ad4b..ca903e2707 100644 --- a/src/3rdparty/harfbuzz-ng/src/hb-subset-instancer-solver.cc +++ b/src/3rdparty/harfbuzz-ng/src/hb-subset-instancer-solver.cc @@ -22,7 +22,7 @@ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. */ -#include "hb.hh" +#include "hb-subset-instancer-solver.hh" /* This file is a straight port of the following: * @@ -32,37 +32,17 @@ * This should be safe. */ -constexpr static float EPSILON = 1.f / (1 << 14); -constexpr static float MAX_F2DOT14 = float (0x7FFF) / (1 << 14); - -struct Triple { - - Triple () : - minimum (0.f), middle (0.f), maximum (0.f) {} - - Triple (float minimum_, float middle_, float maximum_) : - minimum (minimum_), middle (middle_), maximum (maximum_) {} - - bool operator == (const Triple &o) const - { - return minimum == o.minimum && - middle == o.middle && - maximum == o.maximum; - } - - float minimum; - float middle; - float maximum; -}; +constexpr static double EPSILON = 1.0 / (1 << 14); +constexpr static double MAX_F2DOT14 = double (0x7FFF) / (1 << 14); static inline Triple _reverse_negate(const Triple &v) { return {-v.maximum, -v.middle, -v.minimum}; } -static inline float supportScalar (float coord, const Triple &tent) +static inline double supportScalar (double coord, const Triple &tent) { /* Copied from VarRegionAxis::evaluate() */ - float start = tent.minimum, peak = tent.middle, end = tent.maximum; + double start = tent.minimum, peak = tent.middle, end = tent.maximum; if (unlikely (start > peak || peak > end)) return 1.; @@ -82,24 +62,20 @@ static inline float supportScalar (float coord, const Triple &tent) return (end - coord) / (end - peak); } - -using result_item_t = hb_pair_t<float, Triple>; -using result_t = hb_vector_t<result_item_t>; - -static inline result_t +static inline rebase_tent_result_t _solve (Triple tent, Triple axisLimit, bool negative = false) { - float axisMin = axisLimit.minimum; - float axisDef = axisLimit.middle; - float axisMax = axisLimit.maximum; - float lower = tent.minimum; - float peak = tent.middle; - float upper = tent.maximum; + double axisMin = axisLimit.minimum; + double axisDef = axisLimit.middle; + double axisMax = axisLimit.maximum; + double lower = tent.minimum; + double peak = tent.middle; + double upper = tent.maximum; // Mirror the problem such that axisDef <= peak if (axisDef > peak) { - result_t vec = _solve (_reverse_negate (tent), + rebase_tent_result_t vec = _solve (_reverse_negate (tent), _reverse_negate (axisLimit), !negative); @@ -122,10 +98,10 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) * axisMin axisDef axisMax lower upper */ if (axisMax <= lower && axisMax < peak) - return result_t{}; // No overlap + return rebase_tent_result_t{}; // No overlap /* case 2: Only the peak and outermost bound fall outside the new limit; - * we keep the deltaset, update peak and outermost bound and and scale deltas + * we keep the deltaset, update peak and outermost bound and scale deltas * by the scalar value for the restricted axis at the new limit, and solve * recursively. * @@ -154,10 +130,10 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) */ if (axisMax < peak) { - float mult = supportScalar (axisMax, tent); + double mult = supportScalar (axisMax, tent); tent = Triple{lower, axisMax, axisMax}; - result_t vec = _solve (tent, axisLimit); + rebase_tent_result_t vec = _solve (tent, axisLimit); for (auto &p : vec) p = hb_pair (p.first * mult, p.second); @@ -167,13 +143,13 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) // lower <= axisDef <= peak <= axisMax - float gain = supportScalar (axisDef, tent); - result_t out {hb_pair (gain, Triple{})}; + double gain = supportScalar (axisDef, tent); + rebase_tent_result_t out {hb_pair (gain, Triple{})}; // First, the positive side // outGain is the scalar of axisMax at the tent. - float outGain = supportScalar (axisMax, tent); + double outGain = supportScalar (axisMax, tent); /* Case 3a: Gain is more than outGain. The tent down-slope crosses * the axis into negative. We have to split it into multiples. @@ -192,13 +168,15 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) * | * crossing */ - if (gain > outGain) + if (gain >= outGain) { + // Note that this is the branch taken if both gain and outGain are 0. + // Crossing point on the axis. - float crossing = peak + ((1 - gain) * (upper - peak) / (1 - outGain)); + double crossing = peak + (1 - gain) * (upper - peak); - Triple loc{peak, peak, crossing}; - float scalar = 1.f; + Triple loc{hb_max (lower, axisDef), peak, crossing}; + double scalar = 1.0; // The part before the crossing point. out.push (hb_pair (scalar - gain, loc)); @@ -213,7 +191,7 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) if (upper >= axisMax) { Triple loc {crossing, axisMax, axisMax}; - float scalar = supportScalar (axisMax, tent); + double scalar = outGain; out.push (hb_pair (scalar - gain, loc)); } @@ -243,93 +221,89 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) // Downslope. Triple loc1 {crossing, upper, axisMax}; - float scalar1 = 0.f; + double scalar1 = 0.0; // Eternity justify. Triple loc2 {upper, axisMax, axisMax}; - float scalar2 = 1.f; // supportScalar({"tag": axisMax}, {"tag": tent}) + double scalar2 = 0.0; out.push (hb_pair (scalar1 - gain, loc1)); out.push (hb_pair (scalar2 - gain, loc2)); } } - /* Case 3: Outermost limit still fits within F2Dot14 bounds; - * we keep deltas as is and only scale the axes bounds. Deltas beyond -1.0 - * or +1.0 will never be applied as implementations must clamp to that range. - * - * A second tent is needed for cases when gain is positive, though we add it - * unconditionally and it will be dropped because scalar ends up 0. - * - * TODO: See if we can just move upper closer to adjust the slope, instead of - * second tent. - * - * | peak | - * 1.........|............o...|.................. - * | /x\ | - * | /xxx\ | - * | /xxxxx\| - * | /xxxxxxx+ - * | /xxxxxxxx|\ - * 0---|-----|------oxxxxxxxxx|xo---------------1 - * axisMin | lower | upper - * | | - * axisDef axisMax - */ - else if (axisDef + (axisMax - axisDef) * 2 >= upper) + else { - if (!negative && axisDef + (axisMax - axisDef) * MAX_F2DOT14 < upper) - { - // we clamp +2.0 to the max F2Dot14 (~1.99994) for convenience - upper = axisDef + (axisMax - axisDef) * MAX_F2DOT14; - assert (peak < upper); - } - // Special-case if peak is at axisMax. if (axisMax == peak) upper = peak; - Triple loc1 {hb_max (axisDef, lower), peak, upper}; - float scalar1 = 1.f; + /* Case 3: + * we keep deltas as is and only scale the axis upper to achieve + * the desired new tent if feasible. + * + * peak + * 1.....................o.................... + * / \_| + * ..................../....+_.........outGain + * / | \ + * gain..............+......|..+_............. + * /| | | \ + * 0---|-----------o | | | o----------1 + * axisMin lower| | | upper + * | | newUpper + * axisDef axisMax + */ + double newUpper = peak + (1 - gain) * (upper - peak); + assert (axisMax <= newUpper); // Because outGain > gain + /* Disabled because ots doesn't like us: + * https://github.com/fonttools/fonttools/issues/3350 */ - Triple loc2 {peak, upper, upper}; - float scalar2 = 0.f; + if (false && (newUpper <= axisDef + (axisMax - axisDef) * 2)) + { + upper = newUpper; + if (!negative && axisDef + (axisMax - axisDef) * MAX_F2DOT14 < upper) + { + // we clamp +2.0 to the max F2Dot14 (~1.99994) for convenience + upper = axisDef + (axisMax - axisDef) * MAX_F2DOT14; + assert (peak < upper); + } - // Don't add a dirac delta! - if (axisDef < upper) - out.push (hb_pair (scalar1 - gain, loc1)); - if (peak < upper) - out.push (hb_pair (scalar2 - gain, loc2)); - } + Triple loc {hb_max (axisDef, lower), peak, upper}; + double scalar = 1.0; - /* Case 4: New limit doesn't fit; we need to chop into two tents, - * because the shape of a triangle with part of one side cut off - * cannot be represented as a triangle itself. - * - * | peak | - * 1.........|......o.|................... - * | /x\| - * | |xxy|\_ - * | /xxxy| \_ - * | |xxxxy| \_ - * | /xxxxy| \_ - * 0---|-----|-oxxxxxx| o----------1 - * axisMin | lower | upper - * | | - * axisDef axisMax - */ - else - { - Triple loc1 {hb_max (axisDef, lower), peak, axisMax}; - float scalar1 = 1.f; + out.push (hb_pair (scalar - gain, loc)); + } - Triple loc2 {peak, axisMax, axisMax}; - float scalar2 = supportScalar (axisMax, tent); + /* Case 4: New limit doesn't fit; we need to chop into two tents, + * because the shape of a triangle with part of one side cut off + * cannot be represented as a triangle itself. + * + * | peak | + * 1.........|......o.|.................... + * ..........|...../x\|.............outGain + * | |xxy|\_ + * | /xxxy| \_ + * | |xxxxy| \_ + * | /xxxxy| \_ + * 0---|-----|-oxxxxxx| o----------1 + * axisMin | lower | upper + * | | + * axisDef axisMax + */ + else + { + Triple loc1 {hb_max (axisDef, lower), peak, axisMax}; + double scalar1 = 1.0; - out.push (hb_pair (scalar1 - gain, loc1)); - // Don't add a dirac delta! - if (peak < axisMax) - out.push (hb_pair (scalar2 - gain, loc2)); + Triple loc2 {peak, axisMax, axisMax}; + double scalar2 = outGain; + + out.push (hb_pair (scalar1 - gain, loc1)); + // Don't add a dirac delta! + if (peak < axisMax) + out.push (hb_pair (scalar2 - gain, loc2)); + } } /* Now, the negative side @@ -351,7 +325,7 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) if (lower <= axisMin) { Triple loc {axisMin, axisMin, axisDef}; - float scalar = supportScalar (axisMin, tent); + double scalar = supportScalar (axisMin, tent); out.push (hb_pair (scalar - gain, loc)); } @@ -379,11 +353,11 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) // Downslope. Triple loc1 {axisMin, lower, axisDef}; - float scalar1 = 0.f; + double scalar1 = 0.0; // Eternity justify. Triple loc2 {axisMin, axisMin, lower}; - float scalar2 = 0.f; + double scalar2 = 0.0; out.push (hb_pair (scalar1 - gain, loc1)); out.push (hb_pair (scalar2 - gain, loc2)); @@ -392,61 +366,57 @@ _solve (Triple tent, Triple axisLimit, bool negative = false) return out; } -/* Normalizes value based on a min/default/max triple. */ -static inline float normalizeValue (float v, const Triple &triple, bool extrapolate = false) +static inline TripleDistances _reverse_triple_distances (const TripleDistances &v) +{ return TripleDistances (v.positive, v.negative); } + +double renormalizeValue (double v, const Triple &triple, + const TripleDistances &triple_distances, bool extrapolate) { - /* - >>> normalizeValue(400, (100, 400, 900)) - 0.0 - >>> normalizeValue(100, (100, 400, 900)) - -1.0 - >>> normalizeValue(650, (100, 400, 900)) - 0.5 - */ - float lower = triple.minimum, def = triple.middle, upper = triple.maximum; + double lower = triple.minimum, def = triple.middle, upper = triple.maximum; assert (lower <= def && def <= upper); if (!extrapolate) v = hb_max (hb_min (v, upper), lower); - if ((v == def) || (lower == upper)) - return 0.f; + if (v == def) + return 0.0; - if ((v < def && lower != def) || (v > def && upper == def)) + if (def < 0.0) + return -renormalizeValue (-v, _reverse_negate (triple), + _reverse_triple_distances (triple_distances), extrapolate); + + /* default >= 0 and v != default */ + if (v > def) + return (v - def) / (upper - def); + + /* v < def */ + if (lower >= 0.0) return (v - def) / (def - lower); + + /* lower < 0 and v < default */ + double total_distance = triple_distances.negative * (-lower) + triple_distances.positive * def; + + double v_distance; + if (v >= 0.0) + v_distance = (def - v) * triple_distances.positive; else - { - assert ((v > def && upper != def) || - (v < def && lower == def)); - return (v - def) / (upper - def); - } -} + v_distance = (-v) * triple_distances.negative + triple_distances.positive * def; -/* Given a tuple (lower,peak,upper) "tent" and new axis limits - * (axisMin,axisDefault,axisMax), solves how to represent the tent - * under the new axis configuration. All values are in normalized - * -1,0,+1 coordinate system. Tent values can be outside this range. - * - * Return value: a list of tuples. Each tuple is of the form - * (scalar,tent), where scalar is a multipler to multiply any - * delta-sets by, and tent is a new tent for that output delta-set. - * If tent value is Triple{}, that is a special deltaset that should - * be always-enabled (called "gain"). - */ -HB_INTERNAL result_t rebase_tent (Triple tent, Triple axisLimit); + return (-v_distance) /total_distance; +} -result_t -rebase_tent (Triple tent, Triple axisLimit) +rebase_tent_result_t +rebase_tent (Triple tent, Triple axisLimit, TripleDistances axis_triple_distances) { - assert (-1.f <= axisLimit.minimum && axisLimit.minimum <= axisLimit.middle && axisLimit.middle <= axisLimit.maximum && axisLimit.maximum <= +1.f); - assert (-2.f <= tent.minimum && tent.minimum <= tent.middle && tent.middle <= tent.maximum && tent.maximum <= +2.f); - assert (tent.middle != 0.f); + assert (-1.0 <= axisLimit.minimum && axisLimit.minimum <= axisLimit.middle && axisLimit.middle <= axisLimit.maximum && axisLimit.maximum <= +1.0); + assert (-2.0 <= tent.minimum && tent.minimum <= tent.middle && tent.middle <= tent.maximum && tent.maximum <= +2.0); + assert (tent.middle != 0.0); - result_t sols = _solve (tent, axisLimit); + rebase_tent_result_t sols = _solve (tent, axisLimit); - auto n = [&axisLimit] (float v) { return normalizeValue (v, axisLimit, true); }; + auto n = [&axisLimit, &axis_triple_distances] (double v) { return renormalizeValue (v, axisLimit, axis_triple_distances); }; - result_t out; + rebase_tent_result_t out; for (auto &p : sols) { if (!p.first) continue; @@ -460,5 +430,5 @@ rebase_tent (Triple tent, Triple axisLimit) Triple{n (t.minimum), n (t.middle), n (t.maximum)})); } - return sols; + return out; } |