/// <summary>
/// Draws a line on the IPixels between two points.
/// </summary>
/// <param name="pixels">The IPixels to draw on.</param>
/// <param name="rgb">The color of the line.</param>
public static void DrawLine(IPixels pixels,
int x0, int y0, int x1, int y1, int rgb)
{
rgb = rgb & 0xFFFFFF;
//Bresenham line algorithm implementation
int sx = (x0 < x1 ? 1 : -1), sy = (y0 < y1 ? 1 : -1);
int dx = Math.Abs(x1 - x0), dy = Math.Abs(y1 - y0);
int err = dx - dy;
while (true)
{
//set pixel
pixels[y0, x0] = pixels[y0, x0] & (0xFF << 24) | rgb;
//check for break
if (x0 == x1 && y0 == y1) break;
//advance x0 and y0
int err2 = 2 * err;
if (err2 > -dy)
{
err -= dy;
x0 += sx;
}
if (err2 < dx)
{
err += dx;
y0 += sy;
}
}
}
/// <summary>
/// Applies a Shader to the IPixels.
/// </summary>
/// <param name="pixels">The IPixels to shade.</param>
/// <param name="shader">The Shader to apply to the pixels.</param>
public static void Apply(IPixels pixels, Shader shader)
{
for (int row = 0; row < pixels.Height; row++)
{
for (int col = 0; col < pixels.Width; col++)
{
pixels[row, col] = shader(pixels[row, col]);
}
}
}
/// <summary>
/// Constructs a new Selection.
/// </summary>
/// <param name="pixels">The IPixels from which
/// pixels should be selected.</param>
/// <param name="rect">The Rectangle of pixels to use.</param>
public Selection(IPixels pixels, PixRect rect)
{
this.pixels = pixels;
this.rect = rect;
}
/// <summary>
/// Draws a filled rectangle.
/// </summary>
/// <param name="pixels">The IPixels to draw on.</param>
/// <param name="rect">The rectangle to draw.</param>
/// <param name="rgb">The color to use.</param>
public static void FillRect(IPixels pixels, PixRect rect, int rgb)
{
Selection selection = new Selection(pixels, rect);
Shaders.Apply(selection, Shaders.SolidColor(rgb));
}
