背景

Question

感谢您的期待！

背景

我正在每个臂上构建一个四轴飞行器，我已经在其上放置了一条RGB可寻址LED。我使用Arduino来驱动灯光，Arduino代码是C ++，这是一种我不太了解的语言。

Here is the first StackOverflow question我发布了有关此代码的上一个问题。它为您提供了更多关于我正在尝试做什么的背景（如果您有兴趣）。

问题

由于first question的答案，我现在已正确编写了数组“gpsHoldArr”，但我无法访问它的值。

在下面的代码中，我调用toggleLights(gpsHoldArr[x][y])并传入gpsHoldArr的子数组。子阵列应该是指向给定LED条带（[x]）然后指向给定步骤（[y]）的结果。

toggleLights然后应该迭代它传递的数组，并将每个LED的值（1-6中的某个数字）发送到控制台上，并将LED的红色，绿色和蓝色值发送到控制台。

不幸的是，当我运行下面的代码时，我收到此错误： cannot convert int(*)[3] to int* for argument 1 to 'void toggleLights(int*)'

非常感谢任何帮助。

这是当前代码：

//4 arms, 6 steps, 6 leds
int gpsHoldArr[4][6][6][3] = {
  {
    {{255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}}
},
  {
    {{255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}}
},
  {
    {{255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}}
},
  {
    {{255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {0,0,0}},
    {{255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}, {255,0,0}}
}
};

toggleLights(gpsHoldArr[0][0]); //Toggles lights on strip #1, step #1
toggleLights(gpsHoldArr[1][0]); //Toggles lights on strip #2, step #1
toggleLights(gpsHoldArr[2][0]); //Toggles lights on strip #3, step #1
toggleLights(gpsHoldArr[3][0]); //Toggles lights on strip #4, step #1 

void toggleLights(int lights[]){
  for(int i = 0; i <= 6; ++i)
  {
    set_color_led(i, lights[i], lights[i], lights[i]);
  } 
}

void set_color_led(int led, int r, int g, int b){
   Serial.println(led); //Which LED (or "pixel") is it?
   Serial.println(r); //What is the red value?
   Serial.println(g); //What is the green value?
   Serial.println(b); //What is the blue value? 
}

Answer 1

我可能会这样做，在此过程中删除一些重复（宏诡计只是因为Arduino - 在桌面上我会使用类而不是数组。）

struct LED { int r, g, b; };

#define BLACK  {0, 0, 0}
#define RED    {255, 0, 0}

#define DEFAULT_LEDS \
  { {RED, BLACK, BLACK, BLACK, BLACK, BLACK},\
    {RED, RED,   BLACK, BLACK, BLACK, BLACK},\
    {RED, RED,   RED,   BLACK, BLACK, BLACK},\
    {RED, RED,   RED,   RED,   BLACK, BLACK},\
    {RED, RED,   RED,   RED,   RED,   BLACK},\
    {RED, RED,   RED,   RED,   RED,   RED}}

LED gpsHoldArr[4][6][6] = {
   DEFAULT_LEDS,
   DEFAULT_LEDS,
   DEFAULT_LEDS,
   DEFAULT_LEDS
};


void set_color_led(int index, const LED& led){
   Serial.println(index); //Which LED (or "pixel") is it?
   Serial.println(led.r); //What is the red value?
   Serial.println(led.g); //What is the green value?
   Serial.println(led.b); //What is the blue value? 
}

void toggleLights(LED (&leds)[6]){
  for(int i = 0; i < 6; ++i)  // You had a '<=' bug here.
  {
    set_color_led(i, leds[i]);
  } 
}

toggleLights(gpsHoldArr[0][0]); //Toggles lights on strip #1, step #1

Answer 2

当你的函数存在一维数组（衰变为一个指针）时，你传入二维数组。

我可以通过制作结构/类来建议消除数组dimmensions，它会使事情更清晰。

例如

struct Led{
    int r,g,b;
};

void toggleLights(Led lights[]){

Led gpsHoldArr[4][6][6] = 

set_color_led(i, lights[i].r, lights[i].g, lights[i].b);

这应该是您需要进行的所有更改，其余的应该按原样运行。

你可以更进一步，做一个手臂struct和步骤struct。

Answer 3

我不认为toggleLights()正在按照您的想法行事。它的输入是一维数组，但你传递的是一个大小为二维的数组[6] [3]。调用toggleLights(gpsHoldArr[0][0]);时，函数看到的1-D内存数组为{255,0,0,0,0,0}，即数组中的前六个值。然后，对于这些值中的每一个，您调用set_color_led();并为多个参数传递相同的值。在toggleLights()中展开循环，转换为

// set_color_led(i, lights[i], lights[i], lights[i]) for i = {0, ..., 6}
set_color_led(0, 255, 255, 255);
set_color_led(1, 0, 0, 0);
set_color_led(2, 0, 0, 0);
set_color_led(3, 0, 0, 0);
set_color_led(4, 0, 0, 0);
set_color_led(5, 0, 0, 0);
set_color_led(6, 0, 0, 0); // bug here as noted by molbdnilo

这可能不是你想要的。我会将toggleLights()的定义更改为以下内容：

void toggleLights(int lights[][3]){
  for(int i = 0; i < 6; ++i)
  {
    set_color_led(i, lights[i][0], lights[i][1], lights[i][2]);
  } 
}

在这种情况下，当调用toggleLights(gpsHoldArr[0][0]);时，此函数看到的二维数组是

{{255,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}, {0,0,0}}

并在toggleLights()中展开循环，这转换为以下一系列函数调用：

// set_color_led(i, lights[i][0], lights[i][1], lights[i][2]) for i = {0, ..., 5}
set_color_led(0, 255, 0, 0);
set_color_led(1, 0, 0, 0);
set_color_led(2, 0, 0, 0);
set_color_led(3, 0, 0, 0);
set_color_led(4, 0, 0, 0);
set_color_led(5, 0, 0, 0);

在C ++中，如何访问多维数组中的值？

背景

问题

这是当前代码：

3 个答案: