Ejemplo n.º 1
0
std::vector<std::shared_ptr<Shape>> CreateCurveShape(const Transform *o2w,
                                                     const Transform *w2o,
                                                     bool reverseOrientation,
                                                     const ParamSet &params) {
    Float width = params.FindOneFloat("width", 1.f);
    Float width0 = params.FindOneFloat("width0", width);
    Float width1 = params.FindOneFloat("width1", width);

    int ncp;
    const Point3f *cp = params.FindPoint3f("P", &ncp);
    if (ncp != 4) {
        Error(
            "Must provide 4 control points for \"curve\" primitive. "
            "(Provided %d).",
            ncp);
        return std::vector<std::shared_ptr<Shape>>();
    }

    CurveType type;
    std::string curveType = params.FindOneString("type", "flat");
    if (curveType == "flat")
        type = CurveType::Flat;
    else if (curveType == "ribbon")
        type = CurveType::Ribbon;
    else if (curveType == "cylinder")
        type = CurveType::Cylinder;
    else {
        Error("Unknown curve type \"%s\".  Using \"flat\".", curveType.c_str());
        type = CurveType::Cylinder;
    }
    int nnorm;
    const Normal3f *n = params.FindNormal3f("N", &nnorm);
    if (n != nullptr) {
        if (type != CurveType::Ribbon) {
            Warning("Curve normals are only used with \"ribbon\" type curves.");
            n = nullptr;
        } else if (nnorm != 2) {
            Error(
                "Must provide two normals with \"N\" parameter for ribbon "
                "curves. "
                "(Provided %d).",
                nnorm);
            return std::vector<std::shared_ptr<Shape>>();
        }
    }

    int sd = params.FindOneFloat("splitdepth", 2);

    if (type == CurveType::Ribbon && n == nullptr) {
        Error(
            "Must provide normals \"N\" at curve endpoints with ribbon "
            "curves.");
        return std::vector<std::shared_ptr<Shape>>();
    } else
        return CreateCurve(o2w, w2o, reverseOrientation, cp, width0, width1,
                           type, n, sd);
}
Ejemplo n.º 2
0
std::vector<std::shared_ptr<Shape>> CreateNURBS(const Transform *o2w,
                                                const Transform *w2o,
                                                bool reverseOrientation,
                                                const ParamSet &params) {
    int nu = params.FindOneInt("nu", -1);
    if (nu == -1) {
        Error("Must provide number of control points \"nu\" with NURBS shape.");
        return std::vector<std::shared_ptr<Shape>>();
    }

    int uorder = params.FindOneInt("uorder", -1);
    if (uorder == -1) {
        Error("Must provide u order \"uorder\" with NURBS shape.");
        return std::vector<std::shared_ptr<Shape>>();
    }
    int nuknots, nvknots;
    const Float *uknots = params.FindFloat("uknots", &nuknots);
    if (uknots == nullptr) {
        Error("Must provide u knot vector \"uknots\" with NURBS shape.");
        return std::vector<std::shared_ptr<Shape>>();
    }

    if (nuknots != nu + uorder) {
        Error(
            "Number of knots in u knot vector %d doesn't match sum of "
            "number of u control points %d and u order %d.",
            nuknots, nu, uorder);
        return std::vector<std::shared_ptr<Shape>>();
    }

    Float u0 = params.FindOneFloat("u0", uknots[uorder - 1]);
    Float u1 = params.FindOneFloat("u1", uknots[nu]);

    int nv = params.FindOneInt("nv", -1);
    if (nv == -1) {
        Error("Must provide number of control points \"nv\" with NURBS shape.");
        return std::vector<std::shared_ptr<Shape>>();
    }

    int vorder = params.FindOneInt("vorder", -1);
    if (vorder == -1) {
        Error("Must provide v order \"vorder\" with NURBS shape.");
        return std::vector<std::shared_ptr<Shape>>();
    }

    const Float *vknots = params.FindFloat("vknots", &nvknots);
    if (vknots == nullptr) {
        Error("Must provide v knot vector \"vknots\" with NURBS shape.");
        return std::vector<std::shared_ptr<Shape>>();
    }

    if (nvknots != nv + vorder) {
        Error(
            "Number of knots in v knot vector %d doesn't match sum of "
            "number of v control points %d and v order %d.",
            nvknots, nv, vorder);
        return std::vector<std::shared_ptr<Shape>>();
    }

    Float v0 = params.FindOneFloat("v0", vknots[vorder - 1]);
    Float v1 = params.FindOneFloat("v1", vknots[nv]);

    bool isHomogeneous = false;
    int npts;
    const Float *P = (const Float *)params.FindPoint3f("P", &npts);
    if (!P) {
        P = params.FindFloat("Pw", &npts);
        if (!P) {
            Error(
                "Must provide control points via \"P\" or \"Pw\" parameter to "
                "NURBS shape.");
            return std::vector<std::shared_ptr<Shape>>();
        }
        if ((npts % 4) != 0) {
            Error(
                "Number of \"Pw\" control points provided to NURBS shape must "
                "be "
                "multiple of four");
            return std::vector<std::shared_ptr<Shape>>();
        }
        npts /= 4;
        isHomogeneous = true;
    }
    if (npts != nu * nv) {
        Error("NURBS shape was expecting %dx%d=%d control points, was given %d",
              nu, nv, nu * nv, npts);
        return std::vector<std::shared_ptr<Shape>>();
    }

    // Compute NURBS dicing rates
    int diceu = 30, dicev = 30;
    std::unique_ptr<Float[]> ueval(new Float[diceu]);
    std::unique_ptr<Float[]> veval(new Float[dicev]);
    std::unique_ptr<Point3f[]> evalPs(new Point3f[diceu * dicev]);
    std::unique_ptr<Normal3f[]> evalNs(new Normal3f[diceu * dicev]);
    int i;
    for (i = 0; i < diceu; ++i)
        ueval[i] = Lerp((float)i / (float)(diceu - 1), u0, u1);
    for (i = 0; i < dicev; ++i)
        veval[i] = Lerp((float)i / (float)(dicev - 1), v0, v1);

    // Evaluate NURBS over grid of points
    memset(evalPs.get(), 0, diceu * dicev * sizeof(Point3f));
    memset(evalNs.get(), 0, diceu * dicev * sizeof(Point3f));
    std::unique_ptr<Point2f[]> uvs(new Point2f[diceu * dicev]);

    // Turn NURBS into triangles
    std::unique_ptr<Homogeneous3[]> Pw(new Homogeneous3[nu * nv]);
    if (isHomogeneous) {
        for (int i = 0; i < nu * nv; ++i) {
            Pw[i].x = P[4 * i];
            Pw[i].y = P[4 * i + 1];
            Pw[i].z = P[4 * i + 2];
            Pw[i].w = P[4 * i + 3];
        }
    } else {
        for (int i = 0; i < nu * nv; ++i) {
            Pw[i].x = P[3 * i];
            Pw[i].y = P[3 * i + 1];
            Pw[i].z = P[3 * i + 2];
            Pw[i].w = 1.;
        }
    }

    for (int v = 0; v < dicev; ++v) {
        for (int u = 0; u < diceu; ++u) {
            uvs[(v * diceu + u)].x = ueval[u];
            uvs[(v * diceu + u)].y = veval[v];

            Vector3f dpdu, dpdv;
            Point3f pt = NURBSEvaluateSurface(uorder, uknots, nu, ueval[u],
                                              vorder, vknots, nv, veval[v],
                                              Pw.get(), &dpdu, &dpdv);
            evalPs[v * diceu + u].x = pt.x;
            evalPs[v * diceu + u].y = pt.y;
            evalPs[v * diceu + u].z = pt.z;
            evalNs[v * diceu + u] = Normal3f(Normalize(Cross(dpdu, dpdv)));
        }
    }

    // Generate points-polygons mesh
    int nTris = 2 * (diceu - 1) * (dicev - 1);
    std::unique_ptr<int[]> vertices(new int[3 * nTris]);
    int *vertp = vertices.get();
    // Compute the vertex offset numbers for the triangles
    for (int v = 0; v < dicev - 1; ++v) {
        for (int u = 0; u < diceu - 1; ++u) {
#define VN(u, v) ((v)*diceu + (u))
            *vertp++ = VN(u, v);
            *vertp++ = VN(u + 1, v);
            *vertp++ = VN(u + 1, v + 1);

            *vertp++ = VN(u, v);
            *vertp++ = VN(u + 1, v + 1);
            *vertp++ = VN(u, v + 1);
#undef VN
        }
    }
    int nVerts = diceu * dicev;

    return CreateTriangleMesh(o2w, w2o, reverseOrientation, nTris,
                              vertices.get(), nVerts, evalPs.get(), nullptr,
                              evalNs.get(), uvs.get(), nullptr);
}
Ejemplo n.º 3
0
std::vector<std::shared_ptr<Shape>> CreateTriangleMeshShape(
    const Transform *o2w, const Transform *w2o, bool reverseOrientation,
    const ParamSet &params,
    std::map<std::string, std::shared_ptr<Texture<Float>>> *floatTextures) {
    int nvi, npi, nuvi, nsi, nni;
    const int *vi = params.FindInt("indices", &nvi);
    const Point3f *P = params.FindPoint3f("P", &npi);
    const Point2f *uvs = params.FindPoint2f("uv", &nuvi);
    if (!uvs) uvs = params.FindPoint2f("st", &nuvi);
    std::vector<Point2f> tempUVs;
    if (!uvs) {
        const Float *fuv = params.FindFloat("uv", &nuvi);
        if (!fuv) fuv = params.FindFloat("st", &nuvi);
        if (fuv) {
            nuvi /= 2;
            tempUVs.reserve(nuvi);
            for (int i = 0; i < nuvi; ++i)
                tempUVs.push_back(Point2f(fuv[2 * i], fuv[2 * i + 1]));
            uvs = &tempUVs[0];
        }
    }
    bool discardDegenerateUVs =
        params.FindOneBool("discarddegenerateUVs", false);
    if (uvs) {
        if (nuvi < npi) {
            Error(
                "Not enough of \"uv\"s for triangle mesh.  Expencted %d, "
                "found %d.  Discarding.",
                npi, nuvi);
            uvs = nullptr;
        } else if (nuvi > npi)
            Warning(
                "More \"uv\"s provided than will be used for triangle "
                "mesh.  (%d expcted, %d found)",
                npi, nuvi);
    }
    if (!vi) {
        Error(
            "Vertex indices \"indices\" not provided with triangle mesh shape");
        return std::vector<std::shared_ptr<Shape>>();
    }
    if (!P) {
        Error("Vertex positions \"P\" not provided with triangle mesh shape");
        return std::vector<std::shared_ptr<Shape>>();
    }
    const Vector3f *S = params.FindVector3f("S", &nsi);
    if (S && nsi != npi) {
        Error("Number of \"S\"s for triangle mesh must match \"P\"s");
        S = nullptr;
    }
    const Normal3f *N = params.FindNormal3f("N", &nni);
    if (N && nni != npi) {
        Error("Number of \"N\"s for triangle mesh must match \"P\"s");
        N = nullptr;
    }
    if (discardDegenerateUVs && uvs && N) {
        // if there are normals, check for bad uv's that
        // give degenerate mappings; discard them if so
        const int *vp = vi;
        for (int i = 0; i < nvi; i += 3, vp += 3) {
            Float area =
                .5f * Cross(P[vp[0]] - P[vp[1]], P[vp[2]] - P[vp[1]]).Length();
            if (area < 1e-7) continue;  // ignore degenerate tris.
            if ((uvs[vp[0]].x == uvs[vp[1]].x &&
                 uvs[vp[0]].y == uvs[vp[1]].y) ||
                (uvs[vp[1]].x == uvs[vp[2]].x &&
                 uvs[vp[1]].y == uvs[vp[2]].y) ||
                (uvs[vp[2]].x == uvs[vp[0]].x &&
                 uvs[vp[2]].y == uvs[vp[0]].y)) {
                Warning(
                    "Degenerate uv coordinates in triangle mesh.  Discarding "
                    "all uvs.");
                uvs = nullptr;
                break;
            }
        }
    }
    for (int i = 0; i < nvi; ++i)
        if (vi[i] >= npi) {
            Error(
                "trianglemesh has out of-bounds vertex index %d (%d \"P\" "
                "values were given",
                vi[i], npi);
            return std::vector<std::shared_ptr<Shape>>();
        }

    std::shared_ptr<Texture<Float>> alphaTex;
    std::string alphaTexName = params.FindTexture("alpha");
    if (alphaTexName != "") {
        if (floatTextures->find(alphaTexName) != floatTextures->end())
            alphaTex = (*floatTextures)[alphaTexName];
        else
            Error("Couldn't find float texture \"%s\" for \"alpha\" parameter",
                  alphaTexName.c_str());
    } else if (params.FindOneFloat("alpha", 1.f) == 0.f)
        alphaTex.reset(new ConstantTexture<Float>(0.f));

    std::shared_ptr<Texture<Float>> shadowAlphaTex;
    std::string shadowAlphaTexName = params.FindTexture("shadowalpha");
    if (shadowAlphaTexName != "") {
        if (floatTextures->find(shadowAlphaTexName) != floatTextures->end())
            shadowAlphaTex = (*floatTextures)[shadowAlphaTexName];
        else
            Error(
                "Couldn't find float texture \"%s\" for \"shadowalpha\" "
                "parameter",
                shadowAlphaTexName.c_str());
    } else if (params.FindOneFloat("shadowalpha", 1.f) == 0.f)
        shadowAlphaTex.reset(new ConstantTexture<Float>(0.f));

    return CreateTriangleMesh(o2w, w2o, reverseOrientation, nvi / 3, vi, npi, P,
                              S, N, uvs, alphaTex, shadowAlphaTex);
}