blender
/
blender
136
406
Fork 589
Code Issues 6.2k Pull Requests 757 Projects 19 Wiki Activity

Fix T99991: Cycles wrong intercept with new hair curves 

Copy the improved hair curves sync implementation from D14942. That patch is
not ready as a whole but this part was verified to match the old hair particles
can be used already.
This commit is contained in:
Brecht Van Lommel 2022-08-05 19:30:31 +02:00
parent d95100e821
commit 18b703dc05
Notes: blender-bot 2023-02-14 04:56:36 +01:00 
Referenced by commit 871347fd93, Fix Cycles not rendering hair without radius attributes
Referenced by issue #99991, Cycles renders reverse intercept value with new Hair Curves
1 changed files with 72 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

113
intern/cycles/blender/curves.cpp
View File

@ -707,6 +707,21 @@ static void attr_create_motion(Hair *hair, BL::Attribute &b_attribute, const flo
}
}
static void attr_create_uv(AttributeSet &attributes,
BL::Curves &b_curves,
BL::Attribute &b_attribute,
const ustring name)
{
BL::Float2Attribute b_float2_attribute{b_attribute};
Attribute *attr = attributes.add(ATTR_STD_UV, name);
float2 *data = attr->data_float2();
fill_generic_attribute(b_curves, data, ATTR_ELEMENT_CURVE, [&](int i) {
BL::Array<float, 2> v = b_float2_attribute.data[i].vector();
return make_float2(v[0], v[1]);
});
}
static void attr_create_generic(Scene *scene,
Hair *hair,
BL::Curves &b_curves,
@ -715,12 +730,26 @@ static void attr_create_generic(Scene *scene,
{
AttributeSet &attributes = hair->attributes;
static const ustring u_velocity("velocity");
const bool need_uv = hair->need_attribute(scene, ATTR_STD_UV);
bool have_uv = false;
for (BL::Attribute &b_attribute : b_curves.attributes) {
const ustring name{b_attribute.name().c_str()};
const BL::Attribute::domain_enum b_domain = b_attribute.domain();
const BL::Attribute::data_type_enum b_data_type = b_attribute.data_type();
if (need_motion && name == u_velocity) {
attr_create_motion(hair, b_attribute, motion_scale);
continue;
}
/* Weak, use first float2 attribute as standard UV. */
if (need_uv && !have_uv && b_data_type == BL::Attribute::data_type_FLOAT2 &&
b_domain == BL::Attribute::domain_CURVE) {
attr_create_uv(attributes, b_curves, b_attribute, name);
have_uv = true;
continue;
}
if (!hair->need_attribute(scene, name)) {
@ -730,9 +759,6 @@ static void attr_create_generic(Scene *scene,
continue;
}
const BL::Attribute::domain_enum b_domain = b_attribute.domain();
const BL::Attribute::data_type_enum b_data_type = b_attribute.data_type();
AttributeElement element = ATTR_ELEMENT_NONE;
switch (b_domain) {
case BL::Attribute::domain_POINT:
@ -844,79 +870,84 @@ static void export_hair_curves(Scene *scene,
{
/* TODO: optimize so we can straight memcpy arrays from Blender? */
/* Add requested attributes. */
Attribute *attr_intercept = NULL;
Attribute *attr_length = NULL;
Attribute *attr_random = NULL;
if (hair->need_attribute(scene, ATTR_STD_CURVE_INTERCEPT)) {
attr_intercept = hair->attributes.add(ATTR_STD_CURVE_INTERCEPT);
}
if (hair->need_attribute(scene, ATTR_STD_CURVE_LENGTH)) {
attr_length = hair->attributes.add(ATTR_STD_CURVE_LENGTH);
}
if (hair->need_attribute(scene, ATTR_STD_CURVE_RANDOM)) {
attr_random = hair->attributes.add(ATTR_STD_CURVE_RANDOM);
}
/* Reserve memory. */
const int num_keys = b_curves.points.length();
const int num_curves = b_curves.curves.length();
hair->reserve_curves(num_curves, num_keys);
hair->resize_curves(num_curves, num_keys);
float3 *curve_keys = hair->get_curve_keys().data();
float *curve_radius = hair->get_curve_radius().data();
int *curve_first_key = hair->get_curve_first_key().data();
int *curve_shader = hair->get_curve_shader().data();
/* Add requested attributes. */
float *attr_intercept = NULL;
float *attr_length = NULL;
float *attr_random = NULL;
if (hair->need_attribute(scene, ATTR_STD_CURVE_INTERCEPT)) {
attr_intercept = hair->attributes.add(ATTR_STD_CURVE_INTERCEPT)->data_float();
}
if (hair->need_attribute(scene, ATTR_STD_CURVE_LENGTH)) {
attr_length = hair->attributes.add(ATTR_STD_CURVE_LENGTH)->data_float();
}
if (hair->need_attribute(scene, ATTR_STD_CURVE_RANDOM)) {
attr_random = hair->attributes.add(ATTR_STD_CURVE_RANDOM)->data_float();
}
BL::FloatVectorAttribute b_attr_position = find_curves_position_attribute(b_curves);
std::optional<BL::FloatAttribute> b_attr_radius = find_curves_radius_attribute(b_curves);
/* Export curves and points. */
vector<float> points_length;
for (int i = 0; i < num_curves; i++) {
const int first_point_index = b_curves.curve_offset_data[i].value();
const int num_points = b_curves.curve_offset_data[i + 1].value() - first_point_index;
float3 prev_co = zero_float3();
float length = 0.0f;
if (attr_intercept) {
points_length.clear();
points_length.reserve(num_points);
}
/* Position and radius. */
for (int i = 0; i < num_points; i++) {
const float3 co = get_float3(b_attr_position.data[first_point_index + i].vector());
const float radius = b_attr_radius ? b_attr_radius->data[first_point_index + i].value() :
0.005f;
hair->add_curve_key(co, radius);
for (int j = 0; j < num_points; j++) {
const int point_offset = first_point_index + j;
const float3 co = get_float3(b_attr_position.data[point_offset].vector());
const float radius = b_attr_radius ? b_attr_radius->data[point_offset].value() : 0.0f;
if (attr_intercept) {
if (i > 0) {
curve_keys[point_offset] = co;
curve_radius[point_offset] = radius;
if (attr_length || attr_intercept) {
if (j > 0) {
length += len(co - prev_co);
points_length.push_back(length);
}
prev_co = co;
if (attr_intercept) {
attr_intercept[point_offset] = length;
}
}
}
/* Normalized 0..1 attribute along curve. */
if (attr_intercept) {
for (int i = 0; i < num_points; i++) {
attr_intercept->add((length == 0.0f) ? 0.0f : points_length[i] / length);
if (attr_intercept && length > 0.0f) {
for (int j = 1; j < num_points; j++) {
const int point_offset = first_point_index + j;
attr_intercept[point_offset] /= length;
}
}
/* Curve length. */
if (attr_length) {
attr_length->add(length);
attr_length[i] = length;
}
/* Random number per curve. */
if (attr_random != NULL) {
attr_random->add(hash_uint2_to_float(i, 0));
attr_random[i] = hash_uint2_to_float(i, 0);
}
/* Curve. */
const int shader_index = 0;
hair->add_curve(first_point_index, shader_index);
curve_shader[i] = 0;
curve_first_key[i] = first_point_index;
}
attr_create_generic(scene, hair, b_curves, need_motion, motion_scale);