/* * * Copyright © 2006-2009 Simon Thum simon dot thum at gmx dot de * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ #ifdef HAVE_DIX_CONFIG_H #include #endif #include #include #include #include #include /***************************************************************************** * Predictable pointer acceleration * * 2006-2009 by Simon Thum (simon [dot] thum [at] gmx de) * * Serves 3 complementary functions: * 1) provide a sophisticated ballistic velocity estimate to improve * the relation between velocity (of the device) and acceleration * 2) make arbitrary acceleration profiles possible * 3) decelerate by two means (constant and adaptive) if enabled * * Important concepts are the * * - Scheme * which selects the basic algorithm * (see devices.c/InitPointerAccelerationScheme) * - Profile * which returns an acceleration * for a given velocity * * The profile can be selected by the user at runtime. * The classic profile is intended to cleanly perform old-style * function selection (threshold =/!= 0) * ****************************************************************************/ /* fwds */ int SetAccelerationProfile(DeviceVelocityPtr vel, int profile_num); static float SimpleSmoothProfile(DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc); static PointerAccelerationProfileFunc GetAccelerationProfile(DeviceVelocityPtr vel, int profile_num); /*#define PTRACCEL_DEBUGGING*/ #ifdef PTRACCEL_DEBUGGING #define DebugAccelF ErrorF #else #define DebugAccelF(...) /* */ #endif /******************************** * Init/Uninit *******************************/ /* some int which is not a profile number */ #define PROFILE_UNINITIALIZE (-100) /** * Init struct so it should match the average case */ void InitVelocityData(DeviceVelocityPtr vel) { memset(vel, 0, sizeof(DeviceVelocityRec)); vel->corr_mul = 10.0; /* dots per 10 milisecond should be usable */ vel->const_acceleration = 1.0; /* no acceleration/deceleration */ vel->reset_time = 300; vel->use_softening = 1; vel->min_acceleration = 1.0; /* don't decelerate */ vel->max_rel_diff = 0.2; vel->max_diff = 1.0; vel->initial_range = 2; vel->average_accel = TRUE; SetAccelerationProfile(vel, AccelProfileClassic); InitTrackers(vel, 16); } /** * Clean up */ void FreeVelocityData(DeviceVelocityPtr vel){ xfree(vel->tracker); SetAccelerationProfile(vel, PROFILE_UNINITIALIZE); } /* * dix uninit helper, called through scheme */ void AccelerationDefaultCleanup(DeviceIntPtr dev) { /*sanity check*/ if( dev->valuator->accelScheme.AccelSchemeProc == acceleratePointerPredictable && dev->valuator->accelScheme.accelData != NULL){ dev->valuator->accelScheme.AccelSchemeProc = NULL; FreeVelocityData(dev->valuator->accelScheme.accelData); xfree(dev->valuator->accelScheme.accelData); dev->valuator->accelScheme.accelData = NULL; } } /************************* * Input property support ************************/ /** * choose profile */ static int AccelSetProfileProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val, BOOL checkOnly) { DeviceVelocityPtr vel; int profile, *ptr = &profile; int rc; int nelem = 1; if (atom != XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER)) return Success; vel = GetDevicePredictableAccelData(dev); if (!vel) return BadValue; rc = XIPropToInt(val, &nelem, &ptr); if(checkOnly) { if (rc) return rc; if (GetAccelerationProfile(vel, profile) == NULL) return BadValue; } else SetAccelerationProfile(vel, profile); return Success; } static void AccelInitProfileProperty(DeviceIntPtr dev, DeviceVelocityPtr vel) { int profile = vel->statistics.profile_number; Atom prop_profile_number = XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER); XIChangeDeviceProperty(dev, prop_profile_number, XA_INTEGER, 32, PropModeReplace, 1, &profile, FALSE); XISetDevicePropertyDeletable(dev, prop_profile_number, FALSE); XIRegisterPropertyHandler(dev, AccelSetProfileProperty, NULL, NULL); } /** * constant deceleration */ static int AccelSetDecelProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val, BOOL checkOnly) { DeviceVelocityPtr vel; float v, *ptr = &v; int rc; int nelem = 1; if (atom != XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION)) return Success; vel = GetDevicePredictableAccelData(dev); if (!vel) return BadValue; rc = XIPropToFloat(val, &nelem, &ptr); if(checkOnly) { if (rc) return rc; return (v >= 1.0f) ? Success : BadValue; } if(v >= 1.0f) vel->const_acceleration = 1/v; return Success; } static void AccelInitDecelProperty(DeviceIntPtr dev, DeviceVelocityPtr vel) { float fval = 1.0/vel->const_acceleration; Atom prop_const_decel = XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION); XIChangeDeviceProperty(dev, prop_const_decel, XIGetKnownProperty(XATOM_FLOAT), 32, PropModeReplace, 1, &fval, FALSE); XISetDevicePropertyDeletable(dev, prop_const_decel, FALSE); XIRegisterPropertyHandler(dev, AccelSetDecelProperty, NULL, NULL); } /** * adaptive deceleration */ static int AccelSetAdaptDecelProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val, BOOL checkOnly) { DeviceVelocityPtr veloc; float v, *ptr = &v; int rc; int nelem = 1; if (atom != XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION)) return Success; veloc = GetDevicePredictableAccelData(dev); if (!veloc) return BadValue; rc = XIPropToFloat(val, &nelem, &ptr); if(checkOnly) { if (rc) return rc; return (v >= 1.0f) ? Success : BadValue; } if(v >= 1.0f) veloc->min_acceleration = 1/v; return Success; } static void AccelInitAdaptDecelProperty(DeviceIntPtr dev, DeviceVelocityPtr vel) { float fval = 1.0/vel->min_acceleration; Atom prop_adapt_decel = XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION); XIChangeDeviceProperty(dev, prop_adapt_decel, XIGetKnownProperty(XATOM_FLOAT), 32, PropModeReplace, 1, &fval, FALSE); XISetDevicePropertyDeletable(dev, prop_adapt_decel, FALSE); XIRegisterPropertyHandler(dev, AccelSetAdaptDecelProperty, NULL, NULL); } /** * velocity scaling */ static int AccelSetScaleProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val, BOOL checkOnly) { DeviceVelocityPtr vel; float v, *ptr = &v; int rc; int nelem = 1; if (atom != XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING)) return Success; vel = GetDevicePredictableAccelData(dev); if (!vel) return BadValue; rc = XIPropToFloat(val, &nelem, &ptr); if (checkOnly) { if (rc) return rc; return (v > 0) ? Success : BadValue; } if(v > 0) vel->corr_mul = v; return Success; } static void AccelInitScaleProperty(DeviceIntPtr dev, DeviceVelocityPtr vel) { float fval = vel->corr_mul; Atom prop_velo_scale = XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING); XIChangeDeviceProperty(dev, prop_velo_scale, XIGetKnownProperty(XATOM_FLOAT), 32, PropModeReplace, 1, &fval, FALSE); XISetDevicePropertyDeletable(dev, prop_velo_scale, FALSE); XIRegisterPropertyHandler(dev, AccelSetScaleProperty, NULL, NULL); } BOOL InitializePredictableAccelerationProperties(DeviceIntPtr dev) { DeviceVelocityPtr vel = GetDevicePredictableAccelData(dev); if(!vel) return FALSE; AccelInitProfileProperty(dev, vel); AccelInitDecelProperty(dev, vel); AccelInitAdaptDecelProperty(dev, vel); AccelInitScaleProperty(dev, vel); return TRUE; } /********************* * Tracking logic ********************/ void InitTrackers(DeviceVelocityPtr vel, int ntracker) { if(ntracker < 1){ ErrorF("(dix ptracc) invalid number of trackers\n"); return; } xfree(vel->tracker); vel->tracker = (MotionTrackerPtr)xalloc(ntracker * sizeof(MotionTracker)); memset(vel->tracker, 0, ntracker * sizeof(MotionTracker)); vel->num_tracker = ntracker; } /** * return a bit field of possible directions. * 0 = N, 2 = E, 4 = S, 6 = W, in-between is as you guess. * There's no reason against widening to more precise directions (<45 degrees), * should it not perform well. All this is needed for is sort out non-linear * motion, so precision isn't paramount. However, one should not flag direction * too narrow, since it would then cut the linear segment to zero size way too * often. */ static int DoGetDirection(int dx, int dy){ float r; int i1, i2; /* on insignificant mickeys, flag 135 degrees */ if(abs(dx) < 2 && abs(dy < 2)){ /* first check diagonal cases */ if(dx > 0 && dy > 0) return 4+8+16; if(dx > 0 && dy < 0) return 1+2+4; if(dx < 0 && dy < 0) return 1+128+64; if(dx < 0 && dy > 0) return 16+32+64; /* check axis-aligned directions */ if(dx > 0) return 2+4+8; /*E*/ if(dx < 0) return 128+64+32; /*W*/ if(dy > 0) return 32+16+8; /*S*/ if(dy < 0) return 128+1+2; /*N*/ return 255; /* shouldn't happen */ } /* else, compute angle and set appropriate flags */ #ifdef _ISOC99_SOURCE r = atan2f(dy, dx); #else r = atan2(dy, dx); #endif /* find direction. We avoid r to become negative, * since C has no well-defined modulo for such cases. */ r = (r+(M_PI*2.5))/(M_PI/4); /* this intends to flag 2 directions (90 degrees), * except on very well-aligned mickeys. */ i1 = (int)(r+0.1) % 8; i2 = (int)(r+0.9) % 8; if(i1 < 0 || i1 > 7 || i2 < 0 || i2 > 7) return 255; /* shouldn't happen */ return 1 << i1 | 1 << i2; } #define DIRECTION_CACHE_RANGE 5 #define DIRECTION_CACHE_SIZE (DIRECTION_CACHE_RANGE*2+1) /* cache DoGetDirection(). */ static int GetDirection(int dx, int dy){ static int cache[DIRECTION_CACHE_SIZE][DIRECTION_CACHE_SIZE]; int i; if (abs(dx) <= DIRECTION_CACHE_RANGE && abs(dy) <= DIRECTION_CACHE_RANGE) { /* cacheable */ i = cache[DIRECTION_CACHE_RANGE+dx][DIRECTION_CACHE_RANGE+dy]; if(i != 0){ return i; }else{ i = DoGetDirection(dx, dy); cache[DIRECTION_CACHE_RANGE+dx][DIRECTION_CACHE_RANGE+dy] = i; return i; } }else{ /* non-cacheable */ return DoGetDirection(dx, dy); } } #undef DIRECTION_CACHE_RANGE #undef DIRECTION_CACHE_SIZE /* convert offset (age) to array index */ #define TRACKER_INDEX(s, d) (((s)->num_tracker + (s)->cur_tracker - (d)) % (s)->num_tracker) static inline void FeedTrackers(DeviceVelocityPtr vel, int dx, int dy, int cur_t) { int n; for(n = 0; n < vel->num_tracker; n++){ vel->tracker[n].dx += dx; vel->tracker[n].dy += dy; } n = (vel->cur_tracker + 1) % vel->num_tracker; vel->tracker[n].dx = 0; vel->tracker[n].dy = 0; vel->tracker[n].time = cur_t; vel->tracker[n].dir = GetDirection(dx, dy); DebugAccelF("(dix prtacc) motion [dx: %i dy: %i dir:%i diff: %i]\n", dx, dy, vel->tracker[n].dir, cur_t - vel->tracker[vel->cur_tracker].time); vel->cur_tracker = n; } /** * calc velocity for given tracker, with * velocity scaling. * This assumes linear motion. */ static float CalcTracker(DeviceVelocityPtr vel, int offset, int cur_t){ int index = TRACKER_INDEX(vel, offset); float dist = sqrt( vel->tracker[index].dx * vel->tracker[index].dx + vel->tracker[index].dy * vel->tracker[index].dy); int dtime = cur_t - vel->tracker[index].time; if(dtime > 0) return (dist / dtime); else return 0;/* synonymous for NaN, since we're not C99 */ } /* find the most plausible velocity. That is, the most distant * (in time) tracker which isn't too old, beyond a linear partition, * or simply too much off initial velocity. * * May return 0. */ static float QueryTrackers(DeviceVelocityPtr vel, int cur_t){ int n, offset, dir = 255, i = -1, age_ms; /* initial velocity: a low-offset, valid velocity */ float iveloc = 0, res = 0, tmp, vdiff; float vfac = vel->corr_mul * vel->const_acceleration; /* premultiply */ /* loop from current to older data */ for(offset = 1; offset < vel->num_tracker; offset++){ n = TRACKER_INDEX(vel, offset); age_ms = cur_t - vel->tracker[n].time; /* bail out if data is too old and protect from overrun */ if (age_ms >= vel->reset_time || age_ms < 0) { DebugAccelF("(dix prtacc) query: tracker too old\n"); break; } /* * this heuristic avoids using the linear-motion velocity formula * in CalcTracker() on motion that isn't exactly linear. So to get * even more precision we could subdivide as a final step, so possible * non-linearities are accounted for. */ dir &= vel->tracker[n].dir; if(dir == 0){ DebugAccelF("(dix prtacc) query: no longer linear\n"); /* instead of breaking it we might also inspect the partition after, * but actual improvement with this is probably rare. */ break; } tmp = CalcTracker(vel, offset, cur_t) * vfac; if ((iveloc == 0 || offset <= vel->initial_range) && tmp != 0) { /* set initial velocity and result */ res = iveloc = tmp; i = offset; } else if (iveloc != 0 && tmp != 0) { vdiff = fabs(iveloc - tmp); if (vdiff <= vel->max_diff || vdiff/(iveloc + tmp) < vel->max_rel_diff) { /* we're in range with the initial velocity, * so this result is likely better * (it contains more information). */ res = tmp; i = offset; }else{ /* we're not in range, quit - it won't get better. */ DebugAccelF("(dix prtacc) query: tracker too different:" " old %2.2f initial %2.2f diff: %2.2f\n", tmp, iveloc, vdiff); break; } } } if(offset == vel->num_tracker){ DebugAccelF("(dix prtacc) query: last tracker in effect\n"); i = vel->num_tracker-1; } if(i>=0){ n = TRACKER_INDEX(vel, i); DebugAccelF("(dix prtacc) result: offset %i [dx: %i dy: %i diff: %i]\n", i, vel->tracker[n].dx, vel->tracker[n].dy, cur_t - vel->tracker[n].time); } return res; } #undef TRACKER_INDEX /** * Perform velocity approximation based on 2D 'mickeys' (mouse motion delta). * return true if non-visible state reset is suggested */ short ProcessVelocityData2D( DeviceVelocityPtr vel, int dx, int dy, int time) { float velocity; vel->last_velocity = vel->velocity; FeedTrackers(vel, dx, dy, time); velocity = QueryTrackers(vel, time); vel->velocity = velocity; return velocity == 0; } /** * this flattens significant ( > 1) mickeys a little bit for more steady * constant-velocity response */ static inline float ApplySimpleSoftening(int od, int d) { float res = d; if (d <= 1 && d >= -1) return res; if (d > od) res -= 0.5; else if (d < od) res += 0.5; return res; } static void ApplySofteningAndConstantDeceleration( DeviceVelocityPtr vel, int dx, int dy, float* fdx, float* fdy, short do_soften) { if (do_soften && vel->use_softening) { *fdx = ApplySimpleSoftening(vel->last_dx, dx); *fdy = ApplySimpleSoftening(vel->last_dy, dy); } else { *fdx = dx; *fdy = dy; } *fdx *= vel->const_acceleration; *fdy *= vel->const_acceleration; } /* * compute the acceleration for given velocity and enforce min_acceleartion */ float BasicComputeAcceleration( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc){ float result; result = vel->Profile(dev, vel, velocity, threshold, acc); /* enforce min_acceleration */ if (result < vel->min_acceleration) result = vel->min_acceleration; return result; } /** * Compute acceleration. Takes into account averaging, nv-reset, etc. */ static float ComputeAcceleration( DeviceIntPtr dev, DeviceVelocityPtr vel, float threshold, float acc){ float res; if(vel->velocity <= 0){ DebugAccelF("(dix ptracc) profile skipped\n"); /* * If we have no idea about device velocity, don't pretend it. */ return 1; } if(vel->average_accel && vel->velocity != vel->last_velocity){ /* use simpson's rule to average acceleration between * current and previous velocity. * Though being the more natural choice, it causes a minor delay * in comparison, so it can be disabled. */ res = BasicComputeAcceleration( dev, vel, vel->velocity, threshold, acc); res += BasicComputeAcceleration( dev, vel, vel->last_velocity, threshold, acc); res += 4.0f * BasicComputeAcceleration(dev, vel, (vel->last_velocity + vel->velocity) / 2, threshold, acc); res /= 6.0f; DebugAccelF("(dix ptracc) profile average [%.2f ... %.2f] is %.3f\n", vel->velocity, vel->last_velocity, res); return res; }else{ res = BasicComputeAcceleration(dev, vel, vel->velocity, threshold, acc); DebugAccelF("(dix ptracc) profile sample [%.2f] is %.3f\n", vel->velocity, res); return res; } } /***************************************** * Acceleration functions and profiles ****************************************/ /** * Polynomial function similar previous one, but with f(1) = 1 */ static float PolynomialAccelerationProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float ignored, float acc) { return pow(velocity, (acc - 1.0) * 0.5); } /** * returns acceleration for velocity. * This profile selects the two functions like the old scheme did */ static float ClassicProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc) { if (threshold > 0) { return SimpleSmoothProfile (dev, vel, velocity, threshold, acc); } else { return PolynomialAccelerationProfile (dev, vel, velocity, 0, acc); } } /** * Power profile * This has a completely smooth transition curve, i.e. no jumps in the * derivatives. * * This has the expense of overall response dependency on min-acceleration. * In effect, min_acceleration mimics const_acceleration in this profile. */ static float PowerProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc) { float vel_dist; acc = (acc-1.0) * 0.1f + 1.0; /* without this, acc of 2 is unuseable */ if (velocity <= threshold) return vel->min_acceleration; vel_dist = velocity - threshold; return (pow(acc, vel_dist)) * vel->min_acceleration; } /** * just a smooth function in [0..1] -> [0..1] * - point symmetry at 0.5 * - f'(0) = f'(1) = 0 * - starts faster than a sinoid * - smoothness C1 (Cinf if you dare to ignore endpoints) */ static inline float CalcPenumbralGradient(float x){ x *= 2.0f; x -= 1.0f; return 0.5f + (x * sqrt(1.0f - x*x) + asin(x))/M_PI; } /** * acceleration function similar to classic accelerated/unaccelerated, * but with smooth transition in between (and towards zero for adaptive dec.). */ static float SimpleSmoothProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc) { if(velocity < 1.0f) return CalcPenumbralGradient(0.5 + velocity*0.5) * 2.0f - 1.0f; if(threshold < 1.0f) threshold = 1.0f; if (velocity <= threshold) return 1; velocity /= threshold; if (velocity >= acc) return acc; else return 1.0f + (CalcPenumbralGradient(velocity/acc) * (acc - 1.0f)); } /** * This profile uses the first half of the penumbral gradient as a start * and then scales linearly. */ static float SmoothLinearProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc) { float res, nv; if(acc > 1.0f) acc -= 1.0f; /*this is so acc = 1 is no acceleration */ else return 1.0f; nv = (velocity - threshold) * acc * 0.5f; if(nv < 0){ res = 0; }else if(nv < 2){ res = CalcPenumbralGradient(nv*0.25f)*2.0f; }else{ nv -= 2.0f; res = nv * 2.0f / M_PI /* steepness of gradient at 0.5 */ + 1.0f; /* gradient crosses 2|1 */ } res += vel->min_acceleration; return res; } static float LinearProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc) { return acc * velocity; } static float NoProfile( DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity, float threshold, float acc) { return 1.0f; } static PointerAccelerationProfileFunc GetAccelerationProfile( DeviceVelocityPtr vel, int profile_num) { switch(profile_num){ case AccelProfileClassic: return ClassicProfile; case AccelProfileDeviceSpecific: return vel->deviceSpecificProfile; case AccelProfilePolynomial: return PolynomialAccelerationProfile; case AccelProfileSmoothLinear: return SmoothLinearProfile; case AccelProfileSimple: return SimpleSmoothProfile; case AccelProfilePower: return PowerProfile; case AccelProfileLinear: return LinearProfile; case AccelProfileNone: return NoProfile; default: return NULL; } } /** * Set the profile by number. * Intended to make profiles exchangeable at runtime. * If you created a profile, give it a number here and in the header to * make it selectable. In case some profile-specific init is needed, here * would be a good place, since FreeVelocityData() also calls this with * PROFILE_UNINITIALIZE. * * returns FALSE if profile number is unavailable, TRUE otherwise. */ int SetAccelerationProfile( DeviceVelocityPtr vel, int profile_num) { PointerAccelerationProfileFunc profile; profile = GetAccelerationProfile(vel, profile_num); if(profile == NULL && profile_num != PROFILE_UNINITIALIZE) return FALSE; if(vel->profile_private != NULL){ /* Here one could free old profile-private data */ xfree(vel->profile_private); vel->profile_private = NULL; } /* Here one could init profile-private data */ vel->Profile = profile; vel->statistics.profile_number = profile_num; return TRUE; } /********************************************** * driver interaction **********************************************/ /** * device-specific profile * * The device-specific profile is intended as a hook for a driver * which may want to provide an own acceleration profile. * It should not rely on profile-private data, instead * it should do init/uninit in the driver (ie. with DEVICE_INIT and friends). * Users may override or choose it. */ void SetDeviceSpecificAccelerationProfile( DeviceVelocityPtr vel, PointerAccelerationProfileFunc profile) { if(vel) vel->deviceSpecificProfile = profile; } /** * Use this function to obtain a DeviceVelocityPtr for a device. Will return NULL if * the predictable acceleration scheme is not in effect. */ DeviceVelocityPtr GetDevicePredictableAccelData( DeviceIntPtr dev) { /*sanity check*/ if(!dev){ ErrorF("[dix] accel: DeviceIntPtr was NULL"); return NULL; } if( dev->valuator && dev->valuator->accelScheme.AccelSchemeProc == acceleratePointerPredictable && dev->valuator->accelScheme.accelData != NULL){ return (DeviceVelocityPtr)dev->valuator->accelScheme.accelData; } return NULL; } /******************************** * acceleration schemes *******************************/ /** * Modifies valuators in-place. * This version employs a velocity approximation algorithm to * enable fine-grained predictable acceleration profiles. */ void acceleratePointerPredictable( DeviceIntPtr dev, int first_valuator, int num_valuators, int *valuators, int evtime) { float mult = 0.0; int dx = 0, dy = 0; int *px = NULL, *py = NULL; DeviceVelocityPtr velocitydata = (DeviceVelocityPtr) dev->valuator->accelScheme.accelData; float fdx, fdy, tmp; /* no need to init */ Bool soften = TRUE; if (!num_valuators || !valuators || !velocitydata) return; if (velocitydata->statistics.profile_number == AccelProfileNone && velocitydata->const_acceleration == 1.0f) { return; /*we're inactive anyway, so skip the whole thing.*/ } if (first_valuator == 0) { dx = valuators[0]; px = &valuators[0]; } if (first_valuator <= 1 && num_valuators >= (2 - first_valuator)) { dy = valuators[1 - first_valuator]; py = &valuators[1 - first_valuator]; } if (dx || dy){ /* reset non-visible state? */ if (ProcessVelocityData2D(velocitydata, dx , dy, evtime)) { soften = FALSE; } if (dev->ptrfeed && dev->ptrfeed->ctrl.num) { /* invoke acceleration profile to determine acceleration */ mult = ComputeAcceleration (dev, velocitydata, dev->ptrfeed->ctrl.threshold, (float)dev->ptrfeed->ctrl.num / (float)dev->ptrfeed->ctrl.den); if(mult != 1.0 || velocitydata->const_acceleration != 1.0) { ApplySofteningAndConstantDeceleration( velocitydata, dx, dy, &fdx, &fdy, (mult > 1.0) && soften); if (dx) { tmp = mult * fdx + dev->last.remainder[0]; /* Since it may not be apparent: lrintf() does not offer * strong statements about rounding; however because we * process each axis conditionally, there's no danger * of a toggling remainder. Its lack of guarantees likely * makes it faster on the average target. */ *px = lrintf(tmp); dev->last.remainder[0] = tmp - (float)*px; } if (dy) { tmp = mult * fdy + dev->last.remainder[1]; *py = lrintf(tmp); dev->last.remainder[1] = tmp - (float)*py; } DebugAccelF("pos (%i | %i) remainders x: %.3f y: %.3f delta x:%.3f y:%.3f\n", *px, *py, dev->last.remainder[0], dev->last.remainder[1], fdx, fdy); } } } /* remember last motion delta (for softening/slow movement treatment) */ velocitydata->last_dx = dx; velocitydata->last_dy = dy; } /** * Originally a part of xf86PostMotionEvent; modifies valuators * in-place. Retained mostly for embedded scenarios. */ void acceleratePointerLightweight( DeviceIntPtr dev, int first_valuator, int num_valuators, int *valuators, int ignored) { float mult = 0.0; int dx = 0, dy = 0; int *px = NULL, *py = NULL; if (!num_valuators || !valuators) return; if (first_valuator == 0) { dx = valuators[0]; px = &valuators[0]; } if (first_valuator <= 1 && num_valuators >= (2 - first_valuator)) { dy = valuators[1 - first_valuator]; py = &valuators[1 - first_valuator]; } if (!dx && !dy) return; if (dev->ptrfeed && dev->ptrfeed->ctrl.num) { /* modeled from xf86Events.c */ if (dev->ptrfeed->ctrl.threshold) { if ((abs(dx) + abs(dy)) >= dev->ptrfeed->ctrl.threshold) { dev->last.remainder[0] = ((float)dx * (float)(dev->ptrfeed->ctrl.num)) / (float)(dev->ptrfeed->ctrl.den) + dev->last.remainder[0]; if (px) { *px = (int)dev->last.remainder[0]; dev->last.remainder[0] = dev->last.remainder[0] - (float)(*px); } dev->last.remainder[1] = ((float)dy * (float)(dev->ptrfeed->ctrl.num)) / (float)(dev->ptrfeed->ctrl.den) + dev->last.remainder[1]; if (py) { *py = (int)dev->last.remainder[1]; dev->last.remainder[1] = dev->last.remainder[1] - (float)(*py); } } } else { mult = pow((float)dx * (float)dx + (float)dy * (float)dy, ((float)(dev->ptrfeed->ctrl.num) / (float)(dev->ptrfeed->ctrl.den) - 1.0) / 2.0) / 2.0; if (dx) { dev->last.remainder[0] = mult * (float)dx + dev->last.remainder[0]; *px = (int)dev->last.remainder[0]; dev->last.remainder[0] = dev->last.remainder[0] - (float)(*px); } if (dy) { dev->last.remainder[1] = mult * (float)dy + dev->last.remainder[1]; *py = (int)dev->last.remainder[1]; dev->last.remainder[1] = dev->last.remainder[1] - (float)(*py); } } } }