Shapes with structs and arrays

[xeuz]

Hello ladies and gents, my name is xeuz and this is my first post. I'm trying to figure out how to connect the structs to arrays so that i can make shapes starting with an initial grid then changing the colors based on which shape is inputed. any advice would help, thanks!

#include <iostream>
#include <iomanip>
#include <string>

enum class Shapes 
    { FILLED, STRIPES, CHECKERBOARD, SQUARE, X, UPPER_TRI };

enum class Colors 
    { BLACK, WHITE };

struct Pixel { Colors color; };
    struct Pixel b = { Colors BLACK }
    struct Pixel w = { Colors WHITE }

void CreateShape(Pixel p[], int nPixels, Shapes Shape);
    const int Width, Height = 0;
        for (Width = 0; Width < 10; width++)
void Draw ( Pixel p[], int nPixels);

    int iShape [10] = {1,2,3,4,5,6};

Pixel p[2];

int main(){

}

[coder777]

You might do something like this:

enum class Shapes 
    { FILLED, STRIPES, CHECKERBOARD, SQUARE, X, UPPER_TRI };

enum class Colors 
    { BLACK, WHITE };

const int ShapeSizeX = 4;
const int ShapeSizeY = 4;

const Colors FILLEDShapeColors[] = {Colors::WHITE, Colors::WHITE, ....}; // ShapeSizeX * ShapeSizeY

const int GridSizeX = 4;
const int GridSizeY = 4;

Shapes GridShapes[GridSizeX][GridSizeY] = { {Shapes::FILLED, ... }, ... }; // Initial grid / GridSizeX * GridSizeY

void DrawShape(const Colors colors[])
{
...
}

void DrawShape(const Shapes shape)
{
  switch(shape)
  {
    case Shapes::FILLED:
      DrawShape(FILLEDShapeColors);
      break;
...
  }
}

void DrawGrid()
{
  for(int i = 0; i < GridSizeX; ++i)
  {
    for(int j = 0; j < GridSizeY; ++j)
    {
      DrawShape(GridShapes[i][j]);
    }
  }
}

in main()
{
  DrawGrid();
  return 0;
}

Just to give you an idea how to start.

[Handy Andy]

Hello xeuz,

You have a good start.

Using an enum class these lines:

struct Pixel b = { Colors BLACK }
struct Pixel w = { Colors WHITE }

Should be written as:

struct Pixel b = { Colors::BLACK }
struct Pixel w = { Colors::WHITE }

See http://www.cplusplus.com/doc/tutorial/other_data_types/#enum_class

Line 22 should be inside "main". It is best to avoid using global variables like this.

An array like this will work, but a std::vector<Pixel> pixel; is a better choice.

"main" should contain the code to call the functions and direct the program flow.

Line 16 const int Width, Height = 0;. Both variables, as with all regular variables, should start with a lower case letter. Upper case letters are used for "class"es and "struct"s. "width" has no value assigned and "height" is set to zero. Both being defined as a "const" these values can never be changed. The for loop should be giving you an error because you are trying to change a variable that can not be changed. I believe what you want here is: int width{}, height{};. The empty {}s will initialize the variables to zero or you could put a number inside the {}s.

Unless you have a need for "width" outside of the for loop it is better to write the for loop as:for (int width = 0; width < 10; width++). And be careful you started with "Width", but ended with "width++. The difference between the capital and lower case "W" is a completely different variable.

I did not catch this at first, but line 11 ends with a semi-colon which ends the "struct". The next two lines being indented gave the impression that they should belong to the "struct", but they do not.

I think what you meant is:

struct Pixel
{ 
    struct Pixel b = { Color::BLACK }
    struct Pixel w = { Colors::WHITE }
};

With the {}s the "=" is not needed.

Line 15 is a nice prototype. Lines 16 and 17 just because they are indented does not make them part of the function. The semi-colon at the end of line 15 makes it a prototype not a function. Again I think what you meant is:

void CreateShape(Pixel p[], int nPixels, Shapes Shape)
{
    int width, weight = 0;

    for (int width = 0; width < 10; width++)  // <--- better way to write for loop.
    {
        // <--- needs some code here.
    }  //  End for loop.
}  // End function.

The {}s in column 1 make it a function. The for loop needs to do something inside the {}s. And line 3 is not really needed.

And you have the same problem with lines 18 and 20.

As I said you have a good start, but need to fix the problems and add something to "main" to make use of all this.

Hope that helps,

Andy