Open3d——根据距离参数给点云上渐变色

news2025/1/11 23:34:29

找了半天网上都没有开源的根据距离进行点云渐变色上色的代码，所以写一个方便自己和大家的使用~

渐变色生成代码

输入点云shape为[N,3]，我这里使用的是nuScenes数据集，生成的点云使用到中心点的距离作为参数，进行渐变，输出的为[x,y,z,r,g,b]格式的数组，shape为[N,6]，其余的代码通过各种demo即可实现。


def gradient_point_cloud_color_map(points):
    # 根据距离生成色彩
    colors = np.zeros([points.shape[0], 3])
    # 使用x,y计算到中心点的距离
    dist = np.sqrt(np.square(points[:,0]) + np.square(points[:,1]))
    
    dist_max = np.max(dist)
    print(f"dist_max: {dist_max}")
    # 调整渐变半径
    dist = dist / 51.2	# 我这里的半径是51.2m，
    # dist = dist / 2
    
    # RGB
    min = [127,0,255]   # 紫色
    max = [255,255,0]   # 黄色
    
    # 最近处为紫色
    # colors[:,0] = 127
    # colors[:,2] = 255
    
    # 减R(127 -> 0),加G(0->255),再减B(255->0)，再加R(0 -> 255)
    # 127+255+255+255
    all_color_value = 127+255+255+255
    dist_color = dist * all_color_value
    
    # 减R (127 -> 0)
    clr_1 = 127
    dy_r = 127-dist_color
    tmp = np.zeros([colors[dist_color<clr_1].shape[0], 3])
    tmp[:, 0] = dy_r[dist_color<clr_1]
    tmp[:, 1] = 0
    tmp[:, 2] = 255
    colors[dist_color<clr_1] = tmp
    
    # 加G (0->255)
    clr_2 = 127+255
    dy_g = dist_color-clr_1
    tmp = np.zeros([colors[(dist_color>=clr_1) & (dist_color<clr_2)].shape[0], 3])
    tmp[:, 0] = 0
    tmp[:, 1] = dy_g[(dist_color>=clr_1) & (dist_color<clr_2)]
    tmp[:, 2] = 255
    colors[(dist_color>=clr_1) & (dist_color<clr_2)] = tmp
    
    # 减B (255->0)
    clr_3 = 127+255+255
    dy_b = dist_color-clr_2
    tmp = np.zeros([colors[(dist_color>=clr_2) & (dist_color<clr_3)].shape[0], 3])
    tmp[:, 0] = 0
    tmp[:, 1] = 255
    tmp[:, 2] = dy_b[(dist_color>=clr_2) & (dist_color<clr_3)]
    colors[(dist_color>=clr_2) & (dist_color<clr_3)] = tmp
    
    # 加R(0 -> 255)
    clr_4 = 127+255+255+255
    dy_r = dist_color-clr_3
    tmp = np.zeros([colors[(dist_color>=clr_3) & (dist_color<clr_4)].shape[0], 3])
    tmp[:, 0] = dy_r[(dist_color>=clr_3) & (dist_color<clr_4)]
    tmp[:, 1] = 255
    tmp[:, 2] = 0
    colors[(dist_color>=clr_3) & (dist_color<clr_4)] = tmp
    
    '''
    '''
    # 外围都为黄色
    tmp = np.zeros([colors[dist_color>clr_4].shape[0], 3])
    tmp[:, 0] = 255
    tmp[:, 1] = 255
    tmp[:, 2] = 0
    colors[dist_color>clr_4] = tmp
    
    points = np.concatenate((points[:,:3], colors),axis=1)

    return points