public void Can_save_ppm_as_png()
{
// Arrange
// use a string builder to build a 2d image of a gradient
var nx = 200;
var ny = 100;
var rayTracer = new RayTracer(nx, ny);
for (var j = ny - 1; j >= 0; j--)
{
for (var i = 0; i < nx; i++)
{
var col = new Vec3(
(float)i / (float)nx,
(float)j / (float)ny,
51);
var ir = Math.Round(255.99 * col.X);
var ig = Math.Round(255.99 * col.Y);
rayTracer.AddToImageBuffer($"{ir} {ig} {col.Z}");
}
}
// Act
var filename = "test_ppm_as_png.png";
rayTracer.SaveImageFromPPM(filename);
// Assert
Assert.That(VerifyImage("can_save_ppm_as_png_expected_output.png", filename), Is.True);
}
public void Can_Draw_Background()
{
// Arrange
var nx = 200;
var ny = 100;
var rayTracer = new RayTracer(nx, ny);
var lowerBound = new Vec3(-2, -1, -1);
var dx = new Vec3(4, 0, 0);
var dy = new Vec3(0, 2, 0);
var origin = new Vec3(0, 0, 0);
// Act
for (int j = ny - 1; j >= 0; j--)
{
for (int i = 0; i < nx; i++)
{
var u = (double)i / (double)nx;
var v = (double)j / (double)ny;
var currentPoint = lowerBound.Add(dx.Scale(u).Add(dy.Scale(v)));
var ray = new Ray(origin, currentPoint);
var colour = ColourByRay(ray);
var r = (int)(colour.X * 255);
var g = (int)(colour.Y * 255);
var b = (int)(colour.Z * 255);
rayTracer.AddToImageBuffer($"{r} {g} {b}");
}
}
var fileName = "Can_Draw_Background.png";
rayTracer.SaveImageFromPPM(fileName);
// Assert
Assert.That(VerifyImage(fileName, fileName), Is.True);
}