-
Notifications
You must be signed in to change notification settings - Fork 535
/
SKGLView.razor.cs
195 lines (160 loc) · 4.8 KB
/
SKGLView.razor.cs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Components;
using Microsoft.JSInterop;
using SkiaSharp.Views.Blazor.Internal;
namespace SkiaSharp.Views.Blazor
{
public partial class SKGLView : IDisposable
{
private SKHtmlCanvasInterop interop = null!;
private SizeWatcherInterop sizeWatcher = null!;
private DpiWatcherInterop dpiWatcher = null!;
private SKHtmlCanvasInterop.GLInfo jsGLInfo = null!;
private ElementReference htmlCanvas;
private const int ResourceCacheBytes = 256 * 1024 * 1024; // 256 MB
private const SKColorType colorType = SKColorType.Rgba8888;
private const GRSurfaceOrigin surfaceOrigin = GRSurfaceOrigin.BottomLeft;
private GRContext? context;
private GRGlInterface? glInterface;
private GRBackendRenderTarget? renderTarget;
private SKSize renderTargetSize;
private SKSurface? surface;
private SKCanvas? canvas;
private bool enableRenderLoop;
private bool ignorePixelScaling;
private double dpi;
private SKSize canvasSize;
[Inject]
IJSRuntime JS { get; set; } = null!;
[Parameter]
public Action<SKPaintGLSurfaceEventArgs>? OnPaintSurface { get; set; }
[Parameter]
public bool EnableRenderLoop
{
get => enableRenderLoop;
set
{
if (enableRenderLoop != value)
{
enableRenderLoop = value;
Invalidate();
}
}
}
[Parameter]
public bool IgnorePixelScaling
{
get => ignorePixelScaling;
set
{
if (ignorePixelScaling != value)
{
ignorePixelScaling = value;
Invalidate();
}
}
}
[Parameter(CaptureUnmatchedValues = true)]
public IReadOnlyDictionary<string, object>? AdditionalAttributes { get; set; }
public double Dpi => dpi;
protected override async Task OnAfterRenderAsync(bool firstRender)
{
if (firstRender)
{
interop = await SKHtmlCanvasInterop.ImportAsync(JS, htmlCanvas, OnRenderFrame);
jsGLInfo = interop.InitGL();
sizeWatcher = await SizeWatcherInterop.ImportAsync(JS, htmlCanvas, OnSizeChanged);
dpiWatcher = await DpiWatcherInterop.ImportAsync(JS, OnDpiChanged);
}
}
public void Invalidate()
{
if (canvasSize.Width <= 0 || canvasSize.Height <= 0 || dpi <= 0 || jsGLInfo == null)
return;
interop.RequestAnimationFrame(EnableRenderLoop, (int)(canvasSize.Width * dpi), (int)(canvasSize.Height * dpi));
}
private void OnRenderFrame()
{
if (canvasSize.Width <= 0 || canvasSize.Height <= 0 || dpi <= 0 || jsGLInfo == null)
return;
// create the SkiaSharp context
if (context == null)
{
glInterface = GRGlInterface.Create();
context = GRContext.CreateGl(glInterface);
// bump the default resource cache limit
context.SetResourceCacheLimit(ResourceCacheBytes);
}
// get the new surface size
var newSize = CreateSize(out var unscaledSize);
var info = new SKImageInfo(newSize.Width, newSize.Height, colorType);
var userVisibleSize = IgnorePixelScaling ? unscaledSize : info.Size;
// manage the drawing surface
if (renderTarget == null || renderTargetSize != newSize || !renderTarget.IsValid)
{
// create or update the dimensions
renderTargetSize = newSize;
var glInfo = new GRGlFramebufferInfo(jsGLInfo.FboId, colorType.ToGlSizedFormat());
// destroy the old surface
surface?.Dispose();
surface = null;
canvas = null;
// re-create the render target
renderTarget?.Dispose();
renderTarget = new GRBackendRenderTarget(newSize.Width, newSize.Height, jsGLInfo.Samples, jsGLInfo.Stencils, glInfo);
}
// create the surface
if (surface == null)
{
surface = SKSurface.Create(context, renderTarget, surfaceOrigin, colorType);
canvas = surface.Canvas;
}
using (new SKAutoCanvasRestore(canvas, true))
{
if (IgnorePixelScaling)
{
var canvas = surface.Canvas;
canvas.Scale((float)dpi);
canvas.Save();
}
// start drawing
OnPaintSurface?.Invoke(new SKPaintGLSurfaceEventArgs(surface, renderTarget, surfaceOrigin, info.WithSize(userVisibleSize), info));
}
// update the control
canvas?.Flush();
context.Flush();
}
private void OnDpiChanged(double newDpi)
{
dpi = newDpi;
Invalidate();
}
private void OnSizeChanged(SKSize newSize)
{
canvasSize = newSize;
Invalidate();
}
private SKSizeI CreateSize(out SKSizeI unscaledSize)
{
unscaledSize = SKSizeI.Empty;
var w = canvasSize.Width;
var h = canvasSize.Height;
if (!IsPositive(w) || !IsPositive(h))
return SKSizeI.Empty;
unscaledSize = new SKSizeI((int)w, (int)h);
return new SKSizeI((int)(w * dpi), (int)(h * dpi));
static bool IsPositive(double value)
{
return !double.IsNaN(value) && !double.IsInfinity(value) && value > 0;
}
}
public void Dispose()
{
dpiWatcher.Unsubscribe(OnDpiChanged);
sizeWatcher.Dispose();
interop.Dispose();
}
}
}