public static RayImage Render(int width, int height, int samples)
{
// As simple as possible code for now.
var img = new RayImage();
img.Width = width;
img.Height = height;
img.Pixels = new Rgb3f[width * height];
//int samples = 50;
var lookFrom = new Vec3f(5f, 5f, 5f);
var lookAt = new Vec3f(0, 0, -1f);
float dist_to_focus = (lookFrom - lookAt).GetLength();
float aperture = 2.0f;
var cam = new Camera(lookFrom, lookAt, Vec3f.UnitY,
40, (float)width / (float)height, aperture, dist_to_focus);
var drand = new Random();
var world = RandomScene(drand);
//var world = new HitableList(
// new Sphere(new Vec3f(0f, 0f, -1f), 0.5f, new Lambertian(new Vec3f(0.1f, 0.2f, 0.5f))),
// new Sphere(new Vec3f(0, -100.5f, -1f), 100, new Lambertian(new Vec3f(0.8f, 0.8f, 0.0f))),
// new Sphere(new Vec3f(1f, 0f, -1f), 0.5f, new Metal(new Vec3f(0.8f, 0.6f, 0.2f), 0.0f)),
// new Sphere(new Vec3f(-1f, 0f, -1f), 0.5f, new Dielectric(1.5f)),
// new Sphere(new Vec3f(-1f, 0f, -1f), -0.45f, new Dielectric(1.5f))
// );
int cur = 0;
for (int j = height - 1; j >= 0; j--)
{
for (int i = 0; i < width; i++)
{
Vec3f col = Vec3f.Zero;
for (int s = 0; s < samples; s++)
{
float u = (float)(i + drand.NextDouble()) / (float)width;
float v = (float)(j + drand.NextDouble()) / (float)height;
Ray r = cam.GetRay(u, v, drand);
//Vec3f p = r.PointAtParameter(2.0f); // still not used.
col += Color(r, world, 0, drand);
}
col /= (float)samples;
// gamma correction ??
col = new Vec3f(MathF.Sqrt(col.X), MathF.Sqrt(col.Y), MathF.Sqrt(col.Z));
img.Pixels[cur++] = (Rgb3f)col;
//img.Pixels[cur++] = new Rgb3f() { R = r, G = g, B = b };
}
}
return(img);
}
public static bool WriteTga(this RayImage img, Stream output)
{
try
{
var sizeHeader = Marshal.SizeOf <TgaHeader>();
//const int sizeHeader = 18;
var sizePixels = img.Width * img.Height * 3;
var buffer = new byte[sizeHeader + sizePixels];
var span = new Span <byte>(buffer);
// write header.
// IMPORTENT TO USE REF HERE.
ref TgaHeader header = ref MemoryMarshal.Cast <byte, TgaHeader>(span)[0];
//var header = MemoryMarshal.Cast<byte, TgaHeader>(span)[0];
//var header = MemoryMarshal.AsRef<TgaHeader>(span.Slice(0, sizeHeader));
header.DataTypeCode = 2;
header.Width = (short)img.Width;
header.Height = (short)img.Height;
header.BitsPerPixel = 24;
// convert rgb3f to bgr8
var slicePixels = span.Slice(sizeHeader, sizePixels);
FormatUtils.ConvertBGR8(img, ref slicePixels);
output.Write(span);
output.Flush();
return(true);
}
public static bool WritePpm(this RayImage img, Stream output)
{
try
{
using (var writer = new StreamWriter(output))
{
//var writer = new StreamWriter(output);
writer.WriteLine("P3");
writer.WriteLine($"{img.Width} {img.Height}");
writer.WriteLine("255");
foreach (var p in img.Pixels)
{
int ir = (int)(255.99 * p.R);
int ig = (int)(255.99 * p.G);
int ib = (int)(255.99 * p.B);
writer.WriteLine($"{ir} {ig} {ib} ");
}
writer.Flush();
}
return(true);
}
catch (Exception)
{
return(false);
}
}
public static bool WriteBmp(this RayImage img, Stream output)
{
try
{
var sizeFileHeader = Marshal.SizeOf <BmpFileHeader>();
//const int sizeFileHeader = 14;
var sizeInfoHeader = Marshal.SizeOf <BmpInfoHeader>();
//const int sizeInfoHeader = 40;
var sizePixels = img.Width * img.Height * 3;
var buffer = new byte[sizeFileHeader + sizeInfoHeader + sizePixels];
var span = new Span <byte>(buffer);
// write file header.
ref BmpFileHeader fileHeader = ref MemoryMarshal.Cast <byte, BmpFileHeader>(span)[0];
fileHeader.Signature = (int)('B') + ((int)('M') << 8);
fileHeader.FileSize = buffer.Length;
fileHeader.DataOffset = sizeFileHeader + sizeInfoHeader;
// write info header.
ref BmpInfoHeader infoHeader = ref MemoryMarshal.Cast <byte, BmpInfoHeader>(span.Slice(sizeFileHeader, sizeInfoHeader))[0];
public static void ConvertBGR8(RayImage img, ref Span <byte> output, bool FlipHorizontal = false)
{
if (output.Length < (img.Pixels.Length * 3))
{
throw new ArgumentException("output cant hold all of the pixel data...");
}
int cur = 0;
//TODO: Fold this code into single algorithm.
if (FlipHorizontal)
{
for (int y = img.Height - 1; y > 0; y--)
{
int line = y * img.Width;
for (int x = 0; x < img.Width; x++)
{
var p = img.Pixels[line + x];
output[cur++] = (byte)(255.99 * p.B);
output[cur++] = (byte)(255.99 * p.G);
output[cur++] = (byte)(255.99 * p.R);
}
}
}
else
{
foreach (var p in img.Pixels)
{
output[cur++] = (byte)(255.99 * p.B);
output[cur++] = (byte)(255.99 * p.G);
output[cur++] = (byte)(255.99 * p.R);
}
}
}
public static RayImage RenderParallelFor(int width, int height, int samples)
{
// creating image and storage.
var img = new RayImage();
img.Width = width;
img.Height = height;
img.Pixels = new Rgb3f[width * height];
// setting up camera:
var lookFrom = new Vec3f(5f, 5f, 5f);
var lookAt = new Vec3f(0, 0, -1f);
float dist_to_focus = (lookFrom - lookAt).GetLength();
float aperture = 2.0f;
var cam = new Camera(lookFrom, lookAt, Vec3f.UnitY,
40, (float)width / (float)height, aperture, dist_to_focus);
var wrand = new Random();
var world = RandomScene(wrand);
// creating world.
//var world = new HitableList(
// new Sphere(new Vec3f(0f, 0f, -1f), 0.5f, new Lambertian(new Vec3f(0.1f, 0.2f, 0.5f))),
// new Sphere(new Vec3f(0, -100.5f, -1f), 100, new Lambertian(new Vec3f(0.8f, 0.8f, 0.0f))),
// new Sphere(new Vec3f(1f, 0f, -1f), 0.5f, new Metal(new Vec3f(0.8f, 0.6f, 0.2f), 0.0f)),
// new Sphere(new Vec3f(-1f, 0f, -1f), 0.5f, new Dielectric(1.5f)),
// new Sphere(new Vec3f(-1f, 0f, -1f), -0.45f, new Dielectric(1.5f))
// );
// looping height lines.
Parallel.For(0, height - 1, (cur) => {
var j = height - cur - 1; // invert it?
int curLine = cur * width;
var drand = new Random(); // create unique random object for each thread to prevent locking.
for (int i = 0; i < width; i++)
{
Vec3f col = Vec3f.Zero;
for (int s = 0; s < samples; s++)
{
float u = (float)(i + drand.NextDouble()) / (float)width;
float v = (float)(j + drand.NextDouble()) / (float)height;
Ray r = cam.GetRay(u, v, drand);
//Vec3f p = r.PointAtParameter(2.0f); // still not used.
col += Color(r, world, 0, drand);
}
col /= (float)samples;
col = new Vec3f(MathF.Sqrt(col.X), MathF.Sqrt(col.Y), MathF.Sqrt(col.Z));
img.Pixels[curLine + i] = (Rgb3f)col;
//img.Pixels[curLine + i] = new Rgb3f(0.3f, 0.4f, 0.6f);
}
//System.Threading.Thread.Sleep(5);
});
return(img);
}
