asgardius/virtualx-engine
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Handle corner cases for curve baking

Browse source 
When control point and point have equal position,
the derivative is 0 vector, which cause error message in Basis::look_at().
This commit handles this case.
This commit is contained in:
Yaohua Xiong 2022-12-07 23:37:59 +08:00
parent db6976eed4
commit adeef12b12
3 changed files with 36 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
editor/plugins/path_3d_editor_plugin.cpp
View file

@ -274,13 +274,10 @@ void Path3DGizmo::redraw() {
// Fish Bone.
v3p.push_back(p1);
v3p.push_back(p1 + (side - forward) * 0.06);
v3p.push_back(p1 + (side - forward + up * 0.3) * 0.06);
v3p.push_back(p1);
v3p.push_back(p1 + (-side - forward) * 0.06);
v3p.push_back(p1);
v3p.push_back(p1 + up * 0.03);
v3p.push_back(p1 + (-side - forward + up * 0.3) * 0.06);
}
add_lines(v3p, path_material);

38
scene/resources/curve.cpp
View file

@ -790,6 +790,19 @@ void Curve2D::_bake_segment2d_even_length(RBMap<real_t, Vector2> &r_bake, real_t
}
}
Vector2 Curve2D::_calculate_tangent(const Vector2 &p_begin, const Vector2 &p_control_1, const Vector2 &p_control_2, const Vector2 &p_end, const real_t p_t) {
// Handle corner cases.
if (Math::is_zero_approx(p_t - 0.0f) && p_control_1.is_equal_approx(p_begin)) {
return (p_end - p_begin).normalized();
}
if (Math::is_zero_approx(p_t - 1.0f) && p_control_2.is_equal_approx(p_end)) {
return (p_end - p_begin).normalized();
}
return p_begin.bezier_derivative(p_control_1, p_control_2, p_end, p_t).normalized();
}
void Curve2D::_bake() const {
if (!baked_cache_dirty) {
return;
@ -835,19 +848,19 @@ void Curve2D::_bake() const {
// Collect positions and sample tilts and tangents for each baked points.
bpw[0] = points[0].position;
bfw[0] = points[0].position.bezier_derivative(points[0].position + points[0].out, points[1].position + points[1].in, points[1].position, 0.0).normalized();
bfw[0] = _calculate_tangent(points[0].position, points[0].position + points[0].out, points[1].position + points[1].in, points[1].position, 0.0);
int pidx = 0;
for (int i = 0; i < points.size() - 1; i++) {
for (const KeyValue<real_t, Vector2> &E : midpoints[i]) {
pidx++;
bpw[pidx] = E.value;
bfw[pidx] = points[i].position.bezier_derivative(points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, E.key).normalized();
bfw[pidx] = _calculate_tangent(points[i].position, points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, E.key);
}
pidx++;
bpw[pidx] = points[i + 1].position;
bfw[pidx] = points[i].position.bezier_derivative(points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, 1.0).normalized();
bfw[pidx] = _calculate_tangent(points[i].position, points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, 1.0);
}
// Recalculate the baked distances.
@ -1480,6 +1493,19 @@ void Curve3D::_bake_segment3d_even_length(RBMap<real_t, Vector3> &r_bake, real_t
}
}
Vector3 Curve3D::_calculate_tangent(const Vector3 &p_begin, const Vector3 &p_control_1, const Vector3 &p_control_2, const Vector3 &p_end, const real_t p_t) {
// Handle corner cases.
if (Math::is_zero_approx(p_t - 0.0f) && p_control_1.is_equal_approx(p_begin)) {
return (p_end - p_begin).normalized();
}
if (Math::is_zero_approx(p_t - 1.0f) && p_control_2.is_equal_approx(p_end)) {
return (p_end - p_begin).normalized();
}
return p_begin.bezier_derivative(p_control_1, p_control_2, p_end, p_t).normalized();
}
void Curve3D::_bake() const {
if (!baked_cache_dirty) {
return;
@ -1539,7 +1565,7 @@ void Curve3D::_bake() const {
// Collect positions and sample tilts and tangents for each baked points.
bpw[0] = points[0].position;
bfw[0] = points[0].position.bezier_derivative(points[0].position + points[0].out, points[1].position + points[1].in, points[1].position, 0.0).normalized();
bfw[0] = _calculate_tangent(points[0].position, points[0].position + points[0].out, points[1].position + points[1].in, points[1].position, 0.0);
btw[0] = points[0].tilt;
int pidx = 0;
@ -1547,13 +1573,13 @@ void Curve3D::_bake() const {
for (const KeyValue<real_t, Vector3> &E : midpoints[i]) {
pidx++;
bpw[pidx] = E.value;
bfw[pidx] = points[i].position.bezier_derivative(points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, E.key).normalized();
bfw[pidx] = _calculate_tangent(points[i].position, points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, E.key);
btw[pidx] = Math::lerp(points[i].tilt, points[i + 1].tilt, E.key);
}
pidx++;
bpw[pidx] = points[i + 1].position;
bfw[pidx] = points[i].position.bezier_derivative(points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, 1.0).normalized();
bfw[pidx] = _calculate_tangent(points[i].position, points[i].position + points[i].out, points[i + 1].position + points[i + 1].in, points[i + 1].position, 1.0);
btw[pidx] = points[i + 1].tilt;
}

2
scene/resources/curve.h
View file

@ -178,6 +178,7 @@ class Curve2D : public Resource {
void mark_dirty();
static Vector2 _calculate_tangent(const Vector2 &p_begin, const Vector2 &p_control_1, const Vector2 &p_control_2, const Vector2 &p_end, const real_t p_t);
void _bake() const;
real_t bake_interval = 5.0;
@ -261,6 +262,7 @@ class Curve3D : public Resource {
void mark_dirty();
static Vector3 _calculate_tangent(const Vector3 &p_begin, const Vector3 &p_control_1, const Vector3 &p_control_2, const Vector3 &p_end, const real_t p_t);
void _bake() const;
struct Interval {