Fix some naming and comments in F-Curve smoothing code.

This commit is contained in:
Alexander Gavrilov 2020-11-28 14:50:03 +03:00
parent b3f20eed6e
commit c99d767735
3 changed files with 40 additions and 18 deletions

View File

@ -3205,7 +3205,7 @@ static void calchandleNurb_intern(BezTriple *bezt,
const float eps = 1e-5;
/* assume normal handle until we check */
bezt->f5 = HD_AUTOTYPE_NORMAL;
bezt->auto_handle_type = HD_AUTOTYPE_NORMAL;
if (bezt->h1 == 0 && bezt->h2 == 0) {
return;
@ -3298,7 +3298,7 @@ static void calchandleNurb_intern(BezTriple *bezt,
float ydiff2 = next->vec[1][1] - bezt->vec[1][1];
if ((ydiff1 <= 0.0f && ydiff2 <= 0.0f) || (ydiff1 >= 0.0f && ydiff2 >= 0.0f)) {
bezt->vec[0][1] = bezt->vec[1][1];
bezt->f5 = HD_AUTOTYPE_SPECIAL;
bezt->auto_handle_type = HD_AUTOTYPE_LOCKED_FINAL;
}
else { /* handles should not be beyond y coord of two others */
if (ydiff1 <= 0.0f) {
@ -3325,7 +3325,7 @@ static void calchandleNurb_intern(BezTriple *bezt,
float ydiff2 = next->vec[1][1] - bezt->vec[1][1];
if ((ydiff1 <= 0.0f && ydiff2 <= 0.0f) || (ydiff1 >= 0.0f && ydiff2 >= 0.0f)) {
bezt->vec[2][1] = bezt->vec[1][1];
bezt->f5 = HD_AUTOTYPE_SPECIAL;
bezt->auto_handle_type = HD_AUTOTYPE_LOCKED_FINAL;
}
else { /* handles should not be beyond y coord of two others */
if (ydiff1 <= 0.0f) {
@ -3673,24 +3673,33 @@ static bool tridiagonal_solve_with_limits(float *a,
* | | | | | |
* | | | | | |
* | | | | | |
* |-------t1---------t2--------- ~ --------tN-------------------> time (co 0)
* |------dx1--------dx2--------- ~ -------dxN-------------------> time (co 0)
*
* Notation:
*
* x[i], y[i] - keyframe coordinates
* h[i] - right handle y offset from y[i]
*
* dx[i] = x[i] - x[i-1]
* dy[i] = y[i] - y[i-1]
*
* Mathematical basis:
*
* 1. Handle lengths on either side of each point are connected by a factor
* ensuring continuity of the first derivative:
*
* l[i] = t[i+1]/t[i]
* l[i] = dx[i+1]/dx[i]
*
* 2. The tridiagonal system is formed by the following equation, which is derived
* by differentiating the bezier curve and specifies second derivative continuity
* at every point:
*
* l[i]^2 * h[i-1] + (2*l[i]+2) * h[i] + 1/l[i+1] * h[i+1] = (y[i]-y[i-1])*l[i]^2 + y[i+1]-y[i]
* l[i]^2 * h[i-1] + (2*l[i]+2) * h[i] + 1/l[i+1] * h[i+1] = dy[i]*l[i]^2 + dy[i+1]
*
* 3. If this point is adjacent to a manually set handle with X size not equal to 1/3
* of the horizontal interval, this equation becomes slightly more complex:
*
* l[i]^2 * h[i-1] + (3*(1-R[i-1])*l[i] + 3*(1-L[i+1])) * h[i] + 1/l[i+1] * h[i+1] = (y[i]-y[i-1])*l[i]^2 + y[i+1]-y[i]
* l[i]^2 * h[i-1] + (3*(1-R[i-1])*l[i] + 3*(1-L[i+1])) * h[i] + 1/l[i+1] * h[i+1] = dy[i]*l[i]^2 + dy[i+1]
*
* The difference between equations amounts to this, and it's obvious that when R[i-1]
* and L[i+1] are both 1/3, it becomes zero:
@ -3699,6 +3708,14 @@ static bool tridiagonal_solve_with_limits(float *a,
*
* 4. The equations for zero acceleration border conditions are basically the above
* equation with parts omitted, so the handle size correction also applies.
*
* 5. The fully cyclic curve case is handled by eliminating one of the end points,
* and instead of border conditions connecting the curve via a set of equations:
*
* l[0] = l[N] = dx[1] / dx[N]
* dy[0] = dy[N]
* Continuity equation (item 2) for i = 0.
* Substitute h[0] for h[N] and h[N-1] for h[-1]
*/
/* clang-format on */
@ -3801,8 +3818,8 @@ static void bezier_output_handle(BezTriple *bezt, bool right, float dy, bool end
static bool bezier_check_solve_end_handle(BezTriple *bezt, char htype, bool end)
{
return (htype == HD_VECT) ||
(end && ELEM(htype, HD_AUTO, HD_AUTO_ANIM) && bezt->f5 == HD_AUTOTYPE_NORMAL);
return (htype == HD_VECT) || (end && ELEM(htype, HD_AUTO, HD_AUTO_ANIM) &&
bezt->auto_handle_type == HD_AUTOTYPE_NORMAL);
}
static float bezier_calc_handle_adj(float hsize[2], float dx)
@ -3995,7 +4012,7 @@ static void bezier_handle_calc_smooth_fcurve(
static bool is_free_auto_point(BezTriple *bezt)
{
return BEZT_IS_AUTOH(bezt) && bezt->f5 == HD_AUTOTYPE_NORMAL;
return BEZT_IS_AUTOH(bezt) && bezt->auto_handle_type == HD_AUTOTYPE_NORMAL;
}
void BKE_nurb_handle_smooth_fcurve(BezTriple *bezt, int total, bool cyclic)

View File

@ -1285,14 +1285,14 @@ void calchandles_fcurve_ex(FCurve *fcu, eBezTriple_Flag handle_sel_flag)
if (fcu->extend == FCURVE_EXTRAPOLATE_CONSTANT) {
bezt->vec[0][1] = bezt->vec[2][1] = bezt->vec[1][1];
/* Remember that these keyframes are special, they don't need to be adjusted. */
bezt->f5 = HD_AUTOTYPE_SPECIAL;
bezt->auto_handle_type = HD_AUTOTYPE_LOCKED_FINAL;
}
}
}
/* Avoid total smoothing failure on duplicate keyframes (can happen during grab). */
if (prev && prev->vec[1][0] >= bezt->vec[1][0]) {
prev->f5 = bezt->f5 = HD_AUTOTYPE_SPECIAL;
prev->auto_handle_type = bezt->auto_handle_type = HD_AUTOTYPE_LOCKED_FINAL;
}
/* Advance pointers for next iteration. */
@ -1309,10 +1309,11 @@ void calchandles_fcurve_ex(FCurve *fcu, eBezTriple_Flag handle_sel_flag)
}
/* If cyclic extrapolation and Auto Clamp has triggered, ensure it is symmetric. */
if (cycle && (first->f5 != HD_AUTOTYPE_NORMAL || last->f5 != HD_AUTOTYPE_NORMAL)) {
if (cycle && (first->auto_handle_type != HD_AUTOTYPE_NORMAL ||
last->auto_handle_type != HD_AUTOTYPE_NORMAL)) {
first->vec[0][1] = first->vec[2][1] = first->vec[1][1];
last->vec[0][1] = last->vec[2][1] = last->vec[1][1];
first->f5 = last->f5 = HD_AUTOTYPE_SPECIAL;
first->auto_handle_type = last->auto_handle_type = HD_AUTOTYPE_LOCKED_FINAL;
}
/* Do a second pass for auto handle: compute the handle to have 0 acceleration step. */

View File

@ -133,8 +133,8 @@ typedef struct BezTriple {
/** BEZT_IPO_ELASTIC. */
float amplitude, period;
/** F5: used for auto handle to distinguish between normal handle and exception (extrema). */
char f5;
/** Used during auto handle calculation to mark special cases (local extremes). */
char auto_handle_type;
char _pad[3];
} BezTriple;
@ -465,10 +465,14 @@ typedef enum eBezTriple_Handle {
HD_ALIGN_DOUBLESIDE = 5, /* align handles, displayed both of them. used for masks */
} eBezTriple_Handle;
/* f5 (beztriple) */
/* auto_handle_type (beztriple) */
typedef enum eBezTriple_Auto_Type {
/* Normal automatic handle that can be refined further. */
HD_AUTOTYPE_NORMAL = 0,
HD_AUTOTYPE_SPECIAL = 1,
/* Handle locked horizontal due to being an Auto Clamped local
* extreme or a curve endpoint with Constant extrapolation.
* Further smoothing is disabled. */
HD_AUTOTYPE_LOCKED_FINAL = 1,
} eBezTriple_Auto_Type;
/* interpolation modes (used only for BezTriple->ipo) */