Perlin Noise Help

[vivienneanthony]

Hi

I'm trying to use https://github.com/nothings/stb/blob/master/stb_perlin.h for some perlin noise to create a image for a procedural map.

I'm not sure how to use it.

I created the following code that uses it but a little confused how to map it since it uses float. Do I loop through each x,y,z and give the z a new value turning the float to a char(up to 256bit)?

Vivienne

void Image::FreeImageData(unsigned char* pixelData)
{
    if (!pixelData)
        return;

    stbi_image_free(pixelData);
}

bool Image::GeneratePerlin(int width, int height, unsigned components)
{
    // create a location for pixelData
    unsigned char* pixelData;
    int depth;

    // not sure of what the following is
    components=4;       // rgba 4 components
    depth=1;            // meaning 8-bit

    unsigned dataSize = height*width*depth*components;

    // code
    SharedArrayPtr<unsigned char> buffer(new unsigned char[dataSize]);

    // null the memory area
    for(int x=0; x<width; x++)
    {
        for(int y=0; y<height; y++)
        {
            for(int componentsidx=0; componentsidx<components; componentsidx++)
            {
                buffer[x*y*componentsidx]=0;
            }
        }
    }

    // Manipulation here

    // point pixelData to buffer
    pixelData=buffer;

    // set image information
    SetSize(width, height, depth, components);
    SetData(pixelData);
    FreeImageData(pixelData);

    return false;
}

[Avilius]

Why are you taking in components and depth if you're just going to end up hardcoding a set value?

You multiply the unsigned char by a common value.

[vivienneanthony]

I am planning to change it in the future. The code iis modified but I'm getting a cross on the following. Which I'm not sure whats wrong.

void Image::CopyData(const unsigned char* pixelData)
{
    if (!data_)
        return;

    memcpy(data_, pixelData, width_ * height_ * depth_ * components_);
}


Class Info
rivate:
/// Decode an image using stb_image.
static unsigned char* GetImageData(Deserializer& source, int& width, int& height, unsigned& components);
/// Free an image file's pixel data.
static void FreeImageData(unsigned char* pixelData);
/// Width.
int width_;
/// Height.
int height_;
/// Depth.
int depth_;
/// Number of color components.
unsigned components_;
/// Number of compressed mip levels.
unsigned numCompressedLevels_;
/// Compressed format.
CompressedFormat compressedFormat_;
/// Pixel data.
SharedArrayPtr<unsigned char> data_;
/// Precalculated mip level image.
SharedPtr<Image> nextLevel_;
};

[Avilius]

"Class" should be lowercase (eg. class) and you're missing the p on private.