diff options
Diffstat (limited to 'intern/cycles/kernel/geom/curve.h')
| -rw-r--r-- | intern/cycles/kernel/geom/curve.h | 328 |
1 files changed, 328 insertions, 0 deletions
diff --git a/intern/cycles/kernel/geom/curve.h b/intern/cycles/kernel/geom/curve.h new file mode 100644 index 00000000000..7271193eef8 --- /dev/null +++ b/intern/cycles/kernel/geom/curve.h @@ -0,0 +1,328 @@ +/* + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#pragma once + +CCL_NAMESPACE_BEGIN + +/* Curve Primitive + * + * Curve primitive for rendering hair and fur. These can be render as flat + * ribbons or curves with actual thickness. The curve can also be rendered as + * line segments rather than curves for better performance. + */ + +#ifdef __HAIR__ + +/* Reading attributes on various curve elements */ + +ccl_device float curve_attribute_float(KernelGlobals kg, + ccl_private const ShaderData *sd, + const AttributeDescriptor desc, + ccl_private float *dx, + ccl_private float *dy) +{ + if (desc.element & (ATTR_ELEMENT_CURVE_KEY | ATTR_ELEMENT_CURVE_KEY_MOTION)) { + KernelCurve curve = kernel_tex_fetch(__curves, sd->prim); + int k0 = curve.first_key + PRIMITIVE_UNPACK_SEGMENT(sd->type); + int k1 = k0 + 1; + + float f0 = kernel_tex_fetch(__attributes_float, desc.offset + k0); + float f1 = kernel_tex_fetch(__attributes_float, desc.offset + k1); + +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = sd->du.dx * (f1 - f0); + if (dy) + *dy = 0.0f; +# endif + + return (1.0f - sd->u) * f0 + sd->u * f1; + } + else { +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = 0.0f; + if (dy) + *dy = 0.0f; +# endif + + if (desc.element & (ATTR_ELEMENT_CURVE | ATTR_ELEMENT_OBJECT | ATTR_ELEMENT_MESH)) { + const int offset = (desc.element == ATTR_ELEMENT_CURVE) ? desc.offset + sd->prim : + desc.offset; + return kernel_tex_fetch(__attributes_float, offset); + } + else { + return 0.0f; + } + } +} + +ccl_device float2 curve_attribute_float2(KernelGlobals kg, + ccl_private const ShaderData *sd, + const AttributeDescriptor desc, + ccl_private float2 *dx, + ccl_private float2 *dy) +{ + if (desc.element & (ATTR_ELEMENT_CURVE_KEY | ATTR_ELEMENT_CURVE_KEY_MOTION)) { + KernelCurve curve = kernel_tex_fetch(__curves, sd->prim); + int k0 = curve.first_key + PRIMITIVE_UNPACK_SEGMENT(sd->type); + int k1 = k0 + 1; + + float2 f0 = kernel_tex_fetch(__attributes_float2, desc.offset + k0); + float2 f1 = kernel_tex_fetch(__attributes_float2, desc.offset + k1); + +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = sd->du.dx * (f1 - f0); + if (dy) + *dy = make_float2(0.0f, 0.0f); +# endif + + return (1.0f - sd->u) * f0 + sd->u * f1; + } + else { + /* idea: we can't derive any useful differentials here, but for tiled + * mipmap image caching it would be useful to avoid reading the highest + * detail level always. maybe a derivative based on the hair density + * could be computed somehow? */ +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = make_float2(0.0f, 0.0f); + if (dy) + *dy = make_float2(0.0f, 0.0f); +# endif + + if (desc.element & (ATTR_ELEMENT_CURVE | ATTR_ELEMENT_OBJECT | ATTR_ELEMENT_MESH)) { + const int offset = (desc.element == ATTR_ELEMENT_CURVE) ? desc.offset + sd->prim : + desc.offset; + return kernel_tex_fetch(__attributes_float2, offset); + } + else { + return make_float2(0.0f, 0.0f); + } + } +} + +ccl_device float3 curve_attribute_float3(KernelGlobals kg, + ccl_private const ShaderData *sd, + const AttributeDescriptor desc, + ccl_private float3 *dx, + ccl_private float3 *dy) +{ + if (desc.element & (ATTR_ELEMENT_CURVE_KEY | ATTR_ELEMENT_CURVE_KEY_MOTION)) { + KernelCurve curve = kernel_tex_fetch(__curves, sd->prim); + int k0 = curve.first_key + PRIMITIVE_UNPACK_SEGMENT(sd->type); + int k1 = k0 + 1; + + float3 f0 = float4_to_float3(kernel_tex_fetch(__attributes_float3, desc.offset + k0)); + float3 f1 = float4_to_float3(kernel_tex_fetch(__attributes_float3, desc.offset + k1)); + +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = sd->du.dx * (f1 - f0); + if (dy) + *dy = make_float3(0.0f, 0.0f, 0.0f); +# endif + + return (1.0f - sd->u) * f0 + sd->u * f1; + } + else { +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = make_float3(0.0f, 0.0f, 0.0f); + if (dy) + *dy = make_float3(0.0f, 0.0f, 0.0f); +# endif + + if (desc.element & (ATTR_ELEMENT_CURVE | ATTR_ELEMENT_OBJECT | ATTR_ELEMENT_MESH)) { + const int offset = (desc.element == ATTR_ELEMENT_CURVE) ? desc.offset + sd->prim : + desc.offset; + return float4_to_float3(kernel_tex_fetch(__attributes_float3, offset)); + } + else { + return make_float3(0.0f, 0.0f, 0.0f); + } + } +} + +ccl_device float4 curve_attribute_float4(KernelGlobals kg, + ccl_private const ShaderData *sd, + const AttributeDescriptor desc, + ccl_private float4 *dx, + ccl_private float4 *dy) +{ + if (desc.element & (ATTR_ELEMENT_CURVE_KEY | ATTR_ELEMENT_CURVE_KEY_MOTION)) { + KernelCurve curve = kernel_tex_fetch(__curves, sd->prim); + int k0 = curve.first_key + PRIMITIVE_UNPACK_SEGMENT(sd->type); + int k1 = k0 + 1; + + float4 f0 = kernel_tex_fetch(__attributes_float3, desc.offset + k0); + float4 f1 = kernel_tex_fetch(__attributes_float3, desc.offset + k1); + +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = sd->du.dx * (f1 - f0); + if (dy) + *dy = make_float4(0.0f, 0.0f, 0.0f, 0.0f); +# endif + + return (1.0f - sd->u) * f0 + sd->u * f1; + } + else { +# ifdef __RAY_DIFFERENTIALS__ + if (dx) + *dx = make_float4(0.0f, 0.0f, 0.0f, 0.0f); + if (dy) + *dy = make_float4(0.0f, 0.0f, 0.0f, 0.0f); +# endif + + if (desc.element & (ATTR_ELEMENT_CURVE | ATTR_ELEMENT_OBJECT | ATTR_ELEMENT_MESH)) { + const int offset = (desc.element == ATTR_ELEMENT_CURVE) ? desc.offset + sd->prim : + desc.offset; + return kernel_tex_fetch(__attributes_float3, offset); + } + else { + return make_float4(0.0f, 0.0f, 0.0f, 0.0f); + } + } +} + +/* Curve thickness */ + +ccl_device float curve_thickness(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + float r = 0.0f; + + if (sd->type & PRIMITIVE_ALL_CURVE) { + KernelCurve curve = kernel_tex_fetch(__curves, sd->prim); + int k0 = curve.first_key + PRIMITIVE_UNPACK_SEGMENT(sd->type); + int k1 = k0 + 1; + + float4 P_curve[2]; + + if (!(sd->type & PRIMITIVE_ALL_MOTION)) { + P_curve[0] = kernel_tex_fetch(__curve_keys, k0); + P_curve[1] = kernel_tex_fetch(__curve_keys, k1); + } + else { + motion_curve_keys_linear(kg, sd->object, sd->prim, sd->time, k0, k1, P_curve); + } + + r = (P_curve[1].w - P_curve[0].w) * sd->u + P_curve[0].w; + } + + return r * 2.0f; +} + +/* Curve location for motion pass, linear interpolation between keys and + * ignoring radius because we do the same for the motion keys */ + +ccl_device float3 curve_motion_center_location(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + KernelCurve curve = kernel_tex_fetch(__curves, sd->prim); + int k0 = curve.first_key + PRIMITIVE_UNPACK_SEGMENT(sd->type); + int k1 = k0 + 1; + + float4 P_curve[2]; + + P_curve[0] = kernel_tex_fetch(__curve_keys, k0); + P_curve[1] = kernel_tex_fetch(__curve_keys, k1); + + return float4_to_float3(P_curve[1]) * sd->u + float4_to_float3(P_curve[0]) * (1.0f - sd->u); +} + +/* Curve tangent normal */ + +ccl_device float3 curve_tangent_normal(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + float3 tgN = make_float3(0.0f, 0.0f, 0.0f); + + if (sd->type & PRIMITIVE_ALL_CURVE) { + + tgN = -(-sd->I - sd->dPdu * (dot(sd->dPdu, -sd->I) / len_squared(sd->dPdu))); + tgN = normalize(tgN); + + /* need to find suitable scaled gd for corrected normal */ +# if 0 + tgN = normalize(tgN - gd * sd->dPdu); +# endif + } + + return tgN; +} + +/* Curve bounds utility function */ + +ccl_device_inline void curvebounds(ccl_private float *lower, + ccl_private float *upper, + ccl_private float *extremta, + ccl_private float *extrema, + ccl_private float *extremtb, + ccl_private float *extremb, + float p0, + float p1, + float p2, + float p3) +{ + float halfdiscroot = (p2 * p2 - 3 * p3 * p1); + float ta = -1.0f; + float tb = -1.0f; + + *extremta = -1.0f; + *extremtb = -1.0f; + *upper = p0; + *lower = (p0 + p1) + (p2 + p3); + *extrema = *upper; + *extremb = *lower; + + if (*lower >= *upper) { + *upper = *lower; + *lower = p0; + } + + if (halfdiscroot >= 0) { + float inv3p3 = (1.0f / 3.0f) / p3; + halfdiscroot = sqrtf(halfdiscroot); + ta = (-p2 - halfdiscroot) * inv3p3; + tb = (-p2 + halfdiscroot) * inv3p3; + } + + float t2; + float t3; + + if (ta > 0.0f && ta < 1.0f) { + t2 = ta * ta; + t3 = t2 * ta; + *extremta = ta; + *extrema = p3 * t3 + p2 * t2 + p1 * ta + p0; + + *upper = fmaxf(*extrema, *upper); + *lower = fminf(*extrema, *lower); + } + + if (tb > 0.0f && tb < 1.0f) { + t2 = tb * tb; + t3 = t2 * tb; + *extremtb = tb; + *extremb = p3 * t3 + p2 * t2 + p1 * tb + p0; + + *upper = fmaxf(*extremb, *upper); + *lower = fminf(*extremb, *lower); + } +} + +#endif /* __HAIR__ */ + +CCL_NAMESPACE_END |