public void DecodeImageScanlines()
{
var path = Path.Combine(PathToImages, "CMYK.jpg");
var imageHeight = 516;
var fileData = File.ReadAllBytes(path);
var correctBitmap = SKBitmap.Decode(path);
var stream = new SKFileStream(path);
using (var codec = SKCodec.Create(stream)) {
var info = new SKImageInfo(codec.Info.Width, codec.Info.Height);
using (var scanlineBitmap = new SKBitmap(info)) {
scanlineBitmap.Erase(SKColors.Fuchsia);
var result = codec.StartScanlineDecode(info);
Assert.Equal(SKCodecResult.Success, result);
Assert.Equal(SKCodecScanlineOrder.TopDown, codec.ScanlineOrder);
Assert.Equal(0, codec.NextScanline);
// only decode every second line
for (int y = 0; y < info.Height; y += 2)
{
Assert.Equal(1, codec.GetScanlines(scanlineBitmap.GetAddr(0, y), 1, info.RowBytes));
Assert.Equal(y + 1, codec.NextScanline);
if (codec.SkipScanlines(1))
{
Assert.Equal(y + 2, codec.NextScanline);
}
else
{
Assert.Equal(imageHeight, codec.NextScanline); // reached the end
}
}
Assert.False(codec.SkipScanlines(1));
Assert.Equal(imageHeight, codec.NextScanline);
for (var x = 0; x < info.Width; x++)
{
for (var y = 0; y < info.Height; y++)
{
if (y % 2 == 0)
{
Assert.Equal(correctBitmap.GetPixel(x, y), scanlineBitmap.GetPixel(x, y));
}
else
{
Assert.Equal(SKColors.Fuchsia, scanlineBitmap.GetPixel(x, y));
}
}
}
}
}
}
public MainPage()
{
canvasView = new SKCanvasView();
canvasView.PaintSurface += OnCanvasViewPaintSurface;
Content = canvasView;
//1. create bitmap backend for our canvas
_myCanvasBmp = new SKBitmap(800, 600);
//2. create agg render surface and painter
unsafe
{
int *ptr = (int *)_myCanvasBmp.GetAddr(0, 0);
int w = _myCanvasBmp.Width;
int h = _myCanvasBmp.Height;
_actualBmp = new ActualBitmap(w, h, (IntPtr)ptr);
_painter = new AggPainter(new AggRenderSurface(_actualBmp));
_needContentUpdate = true;
}
}
private void PrepareDirect()
{
GL.ClearColor(0f, 0f, 0f, 1f);
CheckErrors();
GL.Enable(EnableCap.Blend);
CheckErrors();
GL.BlendFunc(BlendingFactorSrc.SrcAlpha, BlendingFactorDest.OneMinusSrcAlpha);
CheckErrors();
GL.Enable(EnableCap.Texture2D);
CheckErrors();
GL.EnableClientState(ArrayCap.VertexArray);
CheckErrors();
GL.EnableClientState(ArrayCap.TextureCoordArray);
CheckErrors();
GL.EnableClientState(ArrayCap.ColorArray);
CheckErrors();
GL.Hint(HintTarget.PerspectiveCorrectionHint, HintMode.Nicest);
CheckErrors();
textureIdDirect = GL.GenTexture();
CheckErrors();
GL.BindTexture(TextureTarget.Texture2D, textureIdDirect);
CheckErrors();
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Nearest);
CheckErrors();
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Nearest);
CheckErrors();
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.ClampToEdge);
CheckErrors();
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.ClampToEdge);
CheckErrors();
SKBitmap bitmap = new SKBitmap(100, 100);
for (int x = 0; x < bitmap.Width; x++)
{
for (int y = 0; y < bitmap.Height; y++)
{
bitmap.SetPixel(x, y, SKColors.White);
}
}
bitmap.LockPixels();
GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, bitmap.Width, bitmap.Height,
0, OpenTK.Graphics.OpenGL.PixelFormat.Bgra, PixelType.UnsignedByte, bitmap.GetAddr(0, 0));
CheckErrors();
bitmap.UnlockPixels();
shaderProgram = GL.CreateProgram();
CheckErrors();
int vertexShader = GL.CreateShader(ShaderType.VertexShader);
CheckErrors();
GL.ShaderSource(vertexShader, GetStandardVertexShader());
CheckErrors();
GL.CompileShader(vertexShader);
CheckErrors();
GL.AttachShader(shaderProgram, vertexShader);
CheckErrors();
GL.DeleteShader(vertexShader);
CheckErrors();
int fragmentShader = GL.CreateShader(ShaderType.FragmentShader);
CheckErrors();
GL.ShaderSource(fragmentShader, GetStandardFragmentShader());
CheckErrors();
GL.CompileShader(fragmentShader);
CheckErrors();
GL.AttachShader(shaderProgram, fragmentShader);
CheckErrors();
GL.DeleteShader(fragmentShader);
CheckErrors();
GL.LinkProgram(shaderProgram);
CheckErrors();
var buf1 = GL.GenBuffer();
CheckErrors();
GL.BindBuffer(BufferTarget.ArrayBuffer, buf1);
CheckErrors();
GL.VertexPointer(2, VertexPointerType.Float, GLVertex.Size, 0);
CheckErrors();
GL.TexCoordPointer(2, TexCoordPointerType.Float, GLVertex.Size, Vector2.SizeInBytes);
CheckErrors();
GL.ColorPointer(4, ColorPointerType.Float, GLVertex.Size, Vector2.SizeInBytes * 2);
CheckErrors();
var buf2 = GL.GenBuffer();
CheckErrors();
GL.BindBuffer(BufferTarget.ElementArrayBuffer, buf2);
CheckErrors();
}
