//
// Created by 14727 on 2022/11/7.
//

#include <utility>

#include "NurbsEvaluator.cuh"
#include "cstdio"
#include "utils.h"
//#include "NurbsBasis.cuh"

//extern __device__ void NurbsBasis::d_basisFunction(float *N_Texture, const float *knots, float u, int degree, int d_knotsCnt) {};

__host__ NurbsSurface::Evaluator::Evaluator(std::vector<std::vector<std::vector<float>>> controlPoints,
                                            std::vector<float> knots_u, std::vector<float> knots_v) {
    this->knots_u = std::move(knots_u);
    this->knots_v = std::move(knots_v);
    this->controlPoints = std::move(controlPoints);
    recordTime = false;
    d_nTexture_u = nullptr;
    d_nTexture_v = nullptr;
    d_nTexture1_u = nullptr;
    d_nTexture1_v = nullptr;
    d_knots_u = nullptr;
    d_knots_v = nullptr;
    d_points = nullptr;
}

__host__ std::vector<std::map<std::pair<float, float>, std::vector<float>>>
NurbsSurface::Evaluator::evaluate(int sampleCnt_u_, int sampleCnt_v_) {
    sampleCnt_u = sampleCnt_u_;
    sampleCnt_v = sampleCnt_v_;
    printf("outside  printf..\n");
//    NurbsBasis::myPrint11(1, 3);

    // 构造指向device的controlPoints
    const int pointsCnt_u = controlPoints.size(), pointsCnt_v = controlPoints[0].size(), pointSize = controlPoints[0][0].size();
    const int pointsBytes = pointsCnt_u * pointsCnt_v * pointSize * sizeof(float);
    auto *h_points = (float *) malloc(pointsBytes);
    for (int i = 0; i < pointsCnt_u; i++) {
        for (int j = 0; j < pointsCnt_v; j++) {
            for (int k = 0; k < pointSize; k++) {
                h_points[(i * pointsCnt_v + j) * pointSize + k] = controlPoints[i][j][k];
            }
        }
    }
    cudaMalloc((void **) &d_points, pointsBytes);
    cudaMemcpy(d_points, h_points, pointsBytes, cudaMemcpyHostToDevice);

    // 构造指向device的knots
    const int knotsCnt_u = knots_u.size(), knotsCnt_v = knots_v.size();
    const int knotsBytes_u = knotsCnt_u * sizeof(float), knotsBytes_v = knotsCnt_v * sizeof(float);
    auto *h_knots_u = (float *) malloc(knotsBytes_u), *h_knots_v = (float *) malloc(knotsBytes_v);
    for (int i = 0; i < knotsCnt_u; i++) h_knots_u[i] = knots_u[i];
    for (int i = 0; i < knotsCnt_v; i++) h_knots_v[i] = knots_v[i];

    cudaMalloc((void **) &d_knots_u, knotsBytes_u);
    cudaMalloc((void **) &d_knots_v, knotsBytes_v);
    cudaMemcpy(d_knots_u, h_knots_u, knotsBytes_u, cudaMemcpyHostToDevice);
    cudaMemcpy(d_knots_v, h_knots_v, knotsBytes_v, cudaMemcpyHostToDevice);

    // 构造nTexture
    cudaMalloc((void **) &d_nTexture_u,
               sampleCnt_u * pointsCnt_u * sizeof(float)); // 注意nTexture的大小，在算梯度时用得到i=pointsCnt + 1的基函数值
    cudaMalloc((void **) &d_nTexture_v, sampleCnt_v * pointsCnt_v * sizeof(float));

    // 构造nTexture1
    cudaMalloc((void **) &d_nTexture1_u, sampleCnt_u * (pointsCnt_u + 1) * sizeof(float));
    cudaMalloc((void **) &d_nTexture1_v, sampleCnt_v * (pointsCnt_v + 1) * sizeof(float));

    // 构造g_basisTexture线程层级
    dim3 blockBasis(512);
    dim3 gridBasis_u((sampleCnt_u + blockBasis.x - 1) / blockBasis.x);
    dim3 gridBasis_v((sampleCnt_v + blockBasis.x - 1) / blockBasis.x);

    // 构造线程层级，调用核函数
    dim3 block(32, 32);
    dim3 grid((sampleCnt_u + block.x - 1) / block.x, (sampleCnt_v + block.y - 1) / block.y);
    // 记录用时
    double time_cost_device;
    g_basisTexture<<<gridBasis_u, blockBasis>>>(d_nTexture_u, d_nTexture1_u, d_knots_u, pointsCnt_u, knotsCnt_u,
                                                sampleCnt_u);
    cudaDeviceSynchronize();
    g_basisTexture<<<gridBasis_v, blockBasis>>>(d_nTexture_v, d_nTexture1_v, d_knots_v, pointsCnt_v, knotsCnt_v,
                                                sampleCnt_v);
    cudaDeviceSynchronize();

    if (recordTime) time_cost_device = utils::get_time_windows();
    g_evaluate <<<grid, block>>>(d_nTexture_u, d_nTexture_v, d_points, pointsCnt_u, pointsCnt_v, pointSize,
                                 knots_u[knotsCnt_u - 1], knots_v[knotsCnt_v - 1], sampleCnt_u, sampleCnt_v);
    cudaDeviceSynchronize(); // 所用线程结束后再获取结束时间。cudaThreadSynchronize()在CUDA1.0后被弃用
    if (recordTime) {
        time_cost_device = utils::get_time_windows() - time_cost_device;
        printf("GPU time cost of surface evaluation for %d samples: %lf\n", sampleCnt_u * sampleCnt_v,
               time_cost_device);
    }

    // 释放内存
    free(h_points);
    free(h_knots_u);
    free(h_knots_v);
    printf("First derivatives and normal vectors calculated by GPU:\n");
    derivative();

    cudaDeviceReset();
    return {};
}


__host__ std::vector<std::map<float, std::vector<float>>>
NurbsCurve::Evaluator::evaluate(int sampleCnt_) {
    this->sampleCnt = sampleCnt_;
    // 构造指向device的controlPoints
    const int pointsCnt = controlPoints.size(), pointSize = controlPoints[0].size();
    const int pointsBytes = pointsCnt * pointSize * sizeof(float);
    auto *h_points = (float *) malloc(pointsBytes);
    for (int i = 0; i < pointsCnt; i++) {
        for (int j = 0; j < pointSize; j++) {
            h_points[i * pointSize + j] = controlPoints[i][j];
        }
    }
    cudaMalloc((void **) &d_points, pointsBytes);
    cudaMemcpy(d_points, h_points, pointsBytes, cudaMemcpyHostToDevice);

    // 构造指向device的knots
    const int knotsCnt = knots.size();
    const int knotsBytes = knotsCnt * sizeof(float);
    auto *h_knots = (float *) malloc(knotsBytes);
    for (int i = 0; i < knotsCnt; i++) h_knots[i] = knots[i];
    cudaMalloc((void **) &d_knots, knotsBytes);
    cudaMemcpy(d_knots, h_knots, knotsBytes, cudaMemcpyHostToDevice);

    // 分配nTexture的内存。只需要GPU内存
//    float *d_nTexture = nullptr;
    cudaMalloc((void **) &d_nTexture,
               sampleCnt * pointsCnt * sizeof(float)); // 注意nTexture的大小，在算梯度时用得到i=pointsCnt + 1的基函数值

    // 分配nTexture1的内存。只需要GPU内存
//    float *d_nTexture1 = nullptr;
    cudaMalloc((void **) &d_nTexture1, sampleCnt * (pointsCnt + 1) * sizeof(float));

    // 构造g_basisTexture线程层级
    dim3 blockBasis(512);
    dim3 gridBasis((sampleCnt + blockBasis.x - 1) / blockBasis.x);

    // 构造线程层级
    dim3 block(32, 32);
    dim3 grid((sampleCnt + block.x * block.y - 1) / (block.x * block.y));
    // 记录用时
    double time_cost_device;
    if (recordTime) time_cost_device = utils::get_time_windows();
    printf("there..\n");
    g_basisTexture <<<gridBasis, blockBasis>>>(d_nTexture, d_nTexture1, d_knots, pointsCnt, knotsCnt, sampleCnt);
//    cudaMemcpy(d_nTextureCpy, d_nTexture, nTextureBytes, cudaMemcpyDeviceToDevice); // 有同步功能
    cudaDeviceSynchronize();
    printf("here..\n");
    g_evaluate <<<grid, block>>>(d_nTexture, d_points, pointsCnt, pointSize, knots[knotsCnt - 1], sampleCnt);
//    g_test<<<1,6>>>(d_nTextureCpy);
    cudaDeviceSynchronize(); // 所用线程结束后再获取结束时间。cudaThreadSynchronize()在CUDA1.0后被弃用
    if (recordTime) {
        time_cost_device = utils::get_time_windows() - time_cost_device;
        printf("GPU time cost of curve evaluation for %d samples: %lf\n", sampleCnt, time_cost_device);
    }
    free(h_points);
    free(h_knots);

    printf("First derivatives calculated by GPU:\n");
    derivative();

    cudaDeviceReset();
    return {};
}

__host__ void NurbsSurface::Evaluator::derivative() {
    float *d_derTexture_u = nullptr;
    float *d_derTexture_v = nullptr;
    const int pointsCnt_u = controlPoints.size(), pointsCnt_v = controlPoints[0].size(), pointSize = controlPoints[0][0].size();
    const int knotsCnt_u = knots_u.size(), knotsCnt_v = knots_v.size();
    cudaMalloc((void **) &d_derTexture_u, sampleCnt_u * pointsCnt_u * sizeof(float));
    cudaMalloc((void **) &d_derTexture_v, sampleCnt_v * pointsCnt_v * sizeof(float));

    // 构造线程层级
    dim3 block(32, 32);
    dim3 grid((sampleCnt_u + block.x - 1) / block.x, (sampleCnt_v + block.y - 1) / block.y);
    // 构造g_basisTexture线程层级
    dim3 blockTex(512);
    dim3 gridTex_u((sampleCnt_u + blockTex.x - 1) / blockTex.x);
    dim3 gridTex_v((sampleCnt_v + blockTex.x - 1) / blockTex.x);
    // 记录用时
    double time_cost_device;
    if (recordTime) time_cost_device = utils::get_time_windows();
    g_derTexture<<<gridTex_u, blockTex>>>(d_derTexture_u, d_nTexture1_u, d_knots_u, pointsCnt_u, knotsCnt_u,
                                          sampleCnt_u);
    g_derTexture<<<gridTex_v, blockTex>>>(d_derTexture_v, d_nTexture1_v, d_knots_v, pointsCnt_v, knotsCnt_v,
                                          sampleCnt_v);
    cudaDeviceSynchronize();
    g_derivative<<<grid, block>>>(d_derTexture_u, d_derTexture_v, d_nTexture_u, d_nTexture_v, d_points, pointsCnt_u,
                                  pointsCnt_v, pointSize, knots_u[knotsCnt_u - 1], knots_v[knotsCnt_v - 1], sampleCnt_u,
                                  sampleCnt_v);
    cudaDeviceSynchronize(); // 所用线程结束后再获取结束时间。cudaThreadSynchronize()在CUDA1.0后被弃用
    if (recordTime) {
        time_cost_device = utils::get_time_windows() - time_cost_device;
        printf("GPU time cost of surface first derivative calculating for %d samples: %lf\n", sampleCnt_u * sampleCnt_v,
               time_cost_device);
    }
    cudaFree(d_derTexture_u);
    cudaFree(d_derTexture_v);
}

__host__ void NurbsCurve::Evaluator::derivative() {
    float *d_derTexture = nullptr;
    const int pointsCnt = controlPoints.size(), pointSize = controlPoints[0].size();
    const int knotsCnt = knots.size();
    cudaMalloc((void **) &d_derTexture, sampleCnt * pointsCnt * sizeof(float));

    // 构造线程层级
    dim3 block(32, 32);
    dim3 grid((sampleCnt + block.x * block.y - 1) / (block.x * block.y));
    // 构造g_basisTexture线程层级
    dim3 blockTex(512);
    dim3 gridTex((sampleCnt + blockTex.x - 1) / blockTex.x);
    // 记录用时
    double time_cost_device;
    if (recordTime) time_cost_device = utils::get_time_windows();
    g_derTexture<<<gridTex, blockTex>>>(d_derTexture, d_nTexture1, d_knots, pointsCnt, knotsCnt, sampleCnt);
    cudaDeviceSynchronize();
    g_derivative<<<grid, block>>>(d_derTexture, d_points, pointsCnt, pointSize, knots[knotsCnt - 1], sampleCnt);
    cudaDeviceSynchronize(); // 所用线程结束后再获取结束时间。cudaThreadSynchronize()在CUDA1.0后被弃用
    if (recordTime) {
        time_cost_device = utils::get_time_windows() - time_cost_device;
        printf("GPU time cost of curve first derivative calculating for %d samples: %lf\n", sampleCnt,
               time_cost_device);
    }
    cudaFree(d_derTexture);
}


//__global__ void
//NurbsSurface::g_evaluate(const float *d_points, const float *d_knots_u, const float *d_knots_v,
//                         int d_pointsCnt_u,
//                         int d_pointsCnt_v, int d_pointSize, int d_knotsCnt_u, int d_knotsCnt_v,
//                         int d_sampleCnt_u, int d_sampleCnt_v) {
////    printf(" surface calculating... \n");
//    // 二维grid和二维的block
//    int ix = int(blockIdx.x * blockDim.x + threadIdx.x);
//    int iy = int(blockIdx.y * blockDim.y + threadIdx.y);
//
//    float d_paramCeil_u = d_knots_u[d_knotsCnt_u - 1];
//    float d_paramCeil_v = d_knots_v[d_knotsCnt_v - 1];
//
//    float u = ix * d_paramCeil_u / (d_sampleCnt_u - 1);
//    float v = iy * d_paramCeil_v / (d_sampleCnt_v - 1);
//
//    if (u > 1.0 * d_paramCeil_u || v > 1.0 * d_paramCeil_v) {
//        return;
//    }
//
//    int d_degree_u = d_knotsCnt_u - 1 - d_pointsCnt_u;
//    int d_degree_v = d_knotsCnt_v - 1 - d_pointsCnt_v;
//    // 注意，在device中，全局内存还是以malloc和free的方式分配和回收的，而不是使用cudaMalloc和cudaFree
//    auto *N_Texture_U = (float *) malloc((d_degree_u + 1) * (d_knotsCnt_u - 1) * sizeof(float));
//    auto *N_Texture_V = (float *) malloc((d_degree_v + 1) * (d_knotsCnt_v - 1) * sizeof(float));
//    d_basisFunction(N_Texture_U, d_knots_u, u, d_degree_u, d_knotsCnt_u);
//    d_basisFunction(N_Texture_V, d_knots_v, v, d_degree_v, d_knotsCnt_v);
//    float x = 0., y = 0., z = 0.;
//    for (int i = 0; i < d_pointsCnt_u; i++) {
//        for (int j = 0; j < d_pointsCnt_v; j++) {
//            float N_U = N_Texture_U[d_degree_u * (d_knotsCnt_u - 1) + i];
//            float N_V = N_Texture_V[d_degree_v * (d_knotsCnt_v - 1) + j];
//            int idx = (i * d_pointsCnt_v + j) * d_pointSize;
//            x += N_U * N_V * d_points[idx];
//            y += N_U * N_V * d_points[idx + 1];
//            z += N_U * N_V * d_points[idx + 2];
//        }
//    }
//    printf("(%g, %g)-->(%g, %g, %g)\n", u, v, x, y, z); // %g输出，舍弃无意义的0
//    free(N_Texture_U);
//    free(N_Texture_V);
//}

__global__ void
NurbsSurface::g_evaluate(const float *d_nTexture_u, const float *d_nTexture_v, const float *d_points, int d_pointsCnt_u,
                         int d_pointsCnt_v, int d_pointSize, float d_lastKnot_u, float d_lastKnot_v, int d_sampleCnt_u,
                         int d_sampleCnt_v) {

    // 二维grid和二维的block
    int ix = blockIdx.x * blockDim.x + threadIdx.x;
    int iy = blockIdx.y * blockDim.y + threadIdx.y;

    float u = ix * d_lastKnot_u / (d_sampleCnt_u - 1);
    float v = iy * d_lastKnot_v / (d_sampleCnt_v - 1);

    if (u > 1.0 * d_lastKnot_u || v > 1.0 * d_lastKnot_v) {
        return;
    }

    float x = 0., y = 0., z = 0.;
    for (int i = 0; i < d_pointsCnt_u; i++) {
        float N_U = d_nTexture_u[ix * d_pointsCnt_u + i];
        for (int j = 0; j < d_pointsCnt_v; j++) {
            float N_V = d_nTexture_v[iy * d_pointsCnt_v + j];
            int idx = (i * d_pointsCnt_v + j) * d_pointSize;
            x += N_U * N_V * d_points[idx];
            y += N_U * N_V * d_points[idx + 1];
            z += N_U * N_V * d_points[idx + 2];
        }
    }
    printf("(%g, %g)-->(%g, %g, %g)\n", u, v, x, y, z); // %g输出，舍弃无意义的0
}

__global__ void
NurbsSurface::g_derivative(const float *derTexture_u, const float *derTexture_v, const float *nTexture_u,
                           const float *nTexture_v, const float *d_points, int d_pointsCnt_u, int d_pointsCnt_v,
                           int d_pointSize, float d_lastKnot_u, float d_lastKnot_v, int d_sampleCnt_u,
                           int d_sampleCnt_v) {
    // 二维grid和二维的block
    int ix = blockIdx.x * blockDim.x + threadIdx.x;
    int iy = blockIdx.y * blockDim.y + threadIdx.y;

    if (ix >= d_sampleCnt_u || iy >= d_sampleCnt_v) {
        return;
    }
    float u = ix * d_lastKnot_u / (d_sampleCnt_u - 1);
    float v = iy * d_lastKnot_v / (d_sampleCnt_v - 1);

    float x_u = 0., y_u = 0, z_u = 0.;
    float x_v = 0., y_v = 0, z_v = 0.;

    for (int i = 0; i < d_pointsCnt_u; i++) {
        for (int j = 0; j < d_pointsCnt_u; j++) {
            int baseIdx = (i * d_pointsCnt_v + j) * d_pointSize;
            float factor_u = derTexture_u[ix * d_pointsCnt_u + i] * nTexture_v[iy * d_pointsCnt_v + j];
            float factor_v = derTexture_v[iy * d_pointsCnt_v + j] * nTexture_u[ix * d_pointsCnt_u + i];
            x_u += factor_u * d_points[baseIdx];
            y_u += factor_u * d_points[baseIdx + 1];
            z_u += factor_u * d_points[baseIdx + 2];

            x_v += factor_v * d_points[baseIdx];
            y_v += factor_v * d_points[baseIdx + 1];
            z_v += factor_v * d_points[baseIdx + 2];
        }
    }
    float x_n = y_u * z_v - y_v * z_u, y_n = x_v * z_u - x_u * z_v, z_n = x_u * y_v - x_v * y_u; // 叉乘得到法向量
    printf("(%g,%g)-->u:(%g, %g, %g), v:(%g,%g,%g), normal:(%g,%g,%g)\n", u, v, x_u, y_u, z_u, x_v, y_v, z_v,
           x_n, y_n, z_n);
}

__global__ void
NurbsCurve::g_evaluate(const float *NTexture, const float *d_points, const int d_pointsCnt,
                       const int d_pointSize, const float d_lastKnot, const int d_sampleCnt) {
//    printf(" curve calculating... \n");
    // 二维grid和一维的block
//    int idx = (blockIdx.y * gridDim.x + blockIdx.x) * blockDim.x + threadIdx.x;
    // 二维block和一维grid
    int idx = blockIdx.x * blockDim.x * blockDim.y + threadIdx.y * blockDim.x + threadIdx.x;
    float u = idx * d_lastKnot / (d_sampleCnt - 1);
    if (u > 1.0 * d_lastKnot) {
        return;
    }
//
//    int d_degree = d_knotsCnt - 1 - d_pointsCnt;
//    // 注意，在device中，全局内存还是以malloc和free的方式分配和回收的，而不是使用cudaMalloc和cudaFree
//    auto *N_dp = (float *) malloc((d_degree + 1) * (d_knotsCnt - 1) * sizeof(float));
//    d_basisFunction(N_dp, d_knots, u, d_degree, d_knotsCnt);
    float x = 0., y = 0., z = 0.;
    for (int i = 0; i < d_pointsCnt; i++) {
        float N = NTexture[idx * d_pointsCnt + i];
        int baseIdx = i * d_pointSize;
        x += N * d_points[baseIdx];
        y += N * d_points[baseIdx + 1];
        z += N * d_points[baseIdx + 2];
    }
    printf("(%g)-->(%g, %g, %g)\n", u, x, y, z); // %g输出，舍弃无意义的0
}

__global__ void
NurbsCurve::g_derivative(const float *derTexture, const float *d_points, int d_pointsCnt, int d_pointSize,
                         float d_lastKnot, int d_sampleCnt) {
    // 二维block和一维grid
    int idx = blockIdx.x * blockDim.x * blockDim.y + threadIdx.y * blockDim.x + threadIdx.x;
    if (idx >= d_sampleCnt) return;
    float u = idx * d_lastKnot / (d_sampleCnt - 1);
    float x = 0., y = 0, z = 0.;
//    printf("pointSize: %d\n", d_pointSize);
    for (int i = 0; i < d_pointsCnt; i++) {
        int baseIdx = i * d_pointSize;
        float nFactor = derTexture[idx * d_pointsCnt + i];
        x += nFactor * d_points[baseIdx];
        y += nFactor * d_points[baseIdx + 1];
        z += nFactor * d_points[baseIdx + 2];
//        printf("(x, y, z): (%g, %g, %g)\n", d_points[baseIdx], d_points[baseIdx + 1], d_points[baseIdx + 2]);
    }
    printf("(%g)-->(%g, %g, %g)\n", u, x, y, z);
}

__global__ void g_basisTexture(float *nTexture, float *nTexture1, const float *d_knots, int d_pointsCnt, int d_knotsCnt,
                               int d_sampleCnt) {
    // 一维grid和一维block
    int idx = blockIdx.x * blockDim.x + threadIdx.x;  // 采样点编号
    float d_paramCeil = d_knots[d_knotsCnt - 1];
    float u = idx * d_paramCeil / (d_sampleCnt - 1);
    if (u > 1.0 * d_paramCeil) {
        return;
    }
    int d_degree = d_knotsCnt - 1 - d_pointsCnt;
    auto *N_dp = (float *) malloc((d_degree + 1) * (d_knotsCnt - 1) * sizeof(float));
    d_basisFunction(N_dp, d_knots, u, d_degree, d_knotsCnt);
    for (int i = 0; i < d_pointsCnt; i++) {
        nTexture[idx * d_pointsCnt + i] = N_dp[d_degree * (d_knotsCnt - 1) + i];
        nTexture1[idx * (d_pointsCnt + 1) + i] = N_dp[(d_degree - 1) * (d_knotsCnt - 1) + i];
//        printf("nTexture1: %g ", nTexture1[idx * (d_pointsCnt + 1) + i]);
    }
    nTexture1[idx * (d_pointsCnt + 1) + d_pointsCnt] = N_dp[(d_degree - 1) * (d_knotsCnt - 1) +
                                                            d_pointsCnt]; // nTexture1多记录一列数据
    free(N_dp);
}


__global__ void
g_derTexture(float *derTexture, const float *nTexture1, const float *d_knots, int d_pointsCnt, int d_knotsCnt,
             int d_sampleCnt) {
    // 一维grid和一维block
    int idx = blockIdx.x * blockDim.x + threadIdx.x;  // 采样点编号
    if (idx >= d_sampleCnt) {
        return;
    }
    int degree = d_knotsCnt - 1 - d_pointsCnt;

//    printf("degree: %d\n", degree);
    for (int i = 0; i < d_pointsCnt; i++) {
        float left = d_floatEqual(d_knots[i + degree], d_knots[i]) ? 0 :
                     nTexture1[idx * (d_pointsCnt + 1) + i] * (degree - 1) / (d_knots[i + degree] - d_knots[i]);
        float right = d_floatEqual(d_knots[i + degree + 1], d_knots[i + 1]) ? 0 :
                      nTexture1[idx * (d_pointsCnt + 1) + i + 1] * (degree - 1) /
                      (d_knots[i + degree + 1] - d_knots[i + 1]);
        derTexture[idx * d_pointsCnt + i] = left - right;
//        printf("<%d, %d> -- %g \n", idx, i, left - right);
//        printf("nTex1: %g \n", nTexture1[idx * (d_pointsCnt + 1) + i]);
    }
}

__host__ NurbsCurve::Evaluator::Evaluator(std::vector<std::vector<float>> controlPoints,
                                          std::vector<float> knots) {
    this->knots = std::move(knots);
    this->controlPoints = std::move(controlPoints);
    recordTime = false;
    d_nTexture = nullptr;
    d_nTexture1 = nullptr;

    sampleCnt = 0;
    d_points = nullptr;
    d_knots = nullptr;
}


__device__ void d_basisFunction(float *N_Texture, const float *knots, float u, int degree, int d_knotsCnt) {
    int m = d_knotsCnt - 1;
    for (int p = 0; p <= degree; p++) {
        for (int i = 0; i + p <= m - 1; i++) {
            if (p == 0) {
                if ((u > knots[i] || d_floatEqual(u, knots[i])) && (u < knots[i + 1])
                    ||
                    d_floatEqual(u, knots[i + 1]) && d_floatEqual(u, knots[m])) {
                    N_Texture[p * m + i] = 1.0;
                } else {
                    N_Texture[p * m + i] = 0.0;
                }
            } else {
                float Nip_1 = N_Texture[(p - 1) * m + i];
                float Ni1p_1 = N_Texture[(p - 1) * m + i + 1];
                float left = d_floatEqual(knots[i + p], knots[i]) ? 0 : (u - knots[i]) * Nip_1 /
                                                                        (knots[i + p] - knots[i]);
                float right = d_floatEqual(knots[i + p + 1], knots[i + 1]) ? 0 : (knots[i + p + 1] - u) * Ni1p_1 /
                                                                                 (knots[i + p + 1] - knots[i + 1]);
                N_Texture[p * m + i] = left + right;
            }
        }
    }
}

__device__ bool d_floatEqual(float a, float b) {
    return abs(a - b) < 0.00001;
}


void NurbsCurve::Evaluator::setRecordTime(bool r) {
    recordTime = r;
}

void NurbsSurface::Evaluator::setRecordTime(bool r) {
    recordTime = r;
}

NurbsSurface::Evaluator::~Evaluator() {
    cudaFree(d_nTexture_u);
    cudaFree(d_nTexture_v);
    cudaFree(d_nTexture1_u);
    cudaFree(d_nTexture1_v);
    cudaFree(d_points);
    cudaFree(d_knots_u);
    cudaFree(d_knots_v);
}

NurbsCurve::Evaluator::~Evaluator() {
    cudaFree(d_nTexture);
    cudaFree(d_nTexture1);
    cudaFree(d_points);
    cudaFree(d_knots);
}