Files
OpenRA/OpenRA.Platforms.Default/Sdl2GraphicsContext.cs
2023-10-22 19:51:46 +03:00

292 lines
7.4 KiB
C#

#region Copyright & License Information
/*
* Copyright (c) The OpenRA Developers and Contributors
* This file is part of OpenRA, which is free software. It is made
* available to you under the terms of the GNU General Public License
* as published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version. For more
* information, see COPYING.
*/
#endregion
using System;
using OpenRA.Primitives;
using SDL2;
namespace OpenRA.Platforms.Default
{
sealed class Sdl2GraphicsContext : ThreadAffine, IGraphicsContext
{
readonly Sdl2PlatformWindow window;
IntPtr context;
public string GLVersion => OpenGL.Version;
public Sdl2GraphicsContext(Sdl2PlatformWindow window)
{
this.window = window;
// SDL requires us to create the GL context on the main thread to avoid various platform-specific issues.
// We must then release it from the main thread before we rebind it to the render thread (in InitializeOpenGL below).
context = SDL.SDL_GL_CreateContext(window.Window);
if (context == IntPtr.Zero || SDL.SDL_GL_MakeCurrent(window.Window, IntPtr.Zero) < 0)
throw new InvalidOperationException($"Can not create OpenGL context. (Error: {SDL.SDL_GetError()})");
}
internal void InitializeOpenGL()
{
SetThreadAffinity();
if (SDL.SDL_GL_MakeCurrent(window.Window, context) < 0)
throw new InvalidOperationException($"Can not bind OpenGL context. (Error: {SDL.SDL_GetError()})");
OpenGL.Initialize();
OpenGL.CheckGLError();
OpenGL.glGenVertexArrays(1, out var vao);
OpenGL.CheckGLError();
OpenGL.glBindVertexArray(vao);
OpenGL.CheckGLError();
}
public IVertexBuffer<T> CreateVertexBuffer<T>(int size) where T : struct
{
VerifyThreadAffinity();
return new VertexBuffer<T>(size);
}
public IIndexBuffer CreateIndexBuffer(uint[] indices)
{
VerifyThreadAffinity();
return new StaticIndexBuffer(indices);
}
public T[] CreateVertices<T>(int size) where T : struct
{
VerifyThreadAffinity();
return new T[size];
}
public ITexture CreateTexture()
{
VerifyThreadAffinity();
return new Texture();
}
public IFrameBuffer CreateFrameBuffer(Size s)
{
VerifyThreadAffinity();
return new FrameBuffer(s, new Texture(), Color.FromArgb(0));
}
public IFrameBuffer CreateFrameBuffer(Size s, Color clearColor)
{
VerifyThreadAffinity();
return new FrameBuffer(s, new Texture(), clearColor);
}
public IFrameBuffer CreateFrameBuffer(Size s, ITextureInternal texture, Color clearColor)
{
VerifyThreadAffinity();
return new FrameBuffer(s, texture, clearColor);
}
public IShader CreateShader(IShaderBindings bindings)
{
VerifyThreadAffinity();
return new Shader(bindings);
}
public void EnableScissor(int x, int y, int width, int height)
{
VerifyThreadAffinity();
if (width < 0)
width = 0;
if (height < 0)
height = 0;
var windowSize = window.EffectiveWindowSize;
var windowScale = window.EffectiveWindowScale;
var surfaceSize = window.SurfaceSize;
if (windowSize != surfaceSize)
{
x = (int)Math.Round(windowScale * x);
y = (int)Math.Round(windowScale * y);
width = (int)Math.Round(windowScale * width);
height = (int)Math.Round(windowScale * height);
}
OpenGL.glScissor(x, y, width, height);
OpenGL.CheckGLError();
OpenGL.glEnable(OpenGL.GL_SCISSOR_TEST);
OpenGL.CheckGLError();
}
public void DisableScissor()
{
VerifyThreadAffinity();
OpenGL.glDisable(OpenGL.GL_SCISSOR_TEST);
OpenGL.CheckGLError();
}
public void Present()
{
VerifyThreadAffinity();
SDL.SDL_GL_SwapWindow(window.Window);
}
static int ModeFromPrimitiveType(PrimitiveType pt)
{
switch (pt)
{
case PrimitiveType.PointList: return OpenGL.GL_POINTS;
case PrimitiveType.LineList: return OpenGL.GL_LINES;
case PrimitiveType.TriangleList: return OpenGL.GL_TRIANGLES;
}
throw new NotImplementedException();
}
public void DrawPrimitives(PrimitiveType pt, int firstVertex, int numVertices)
{
VerifyThreadAffinity();
OpenGL.glDrawArrays(ModeFromPrimitiveType(pt), firstVertex, numVertices);
OpenGL.CheckGLError();
}
public void DrawElements(int numIndices, int offset)
{
VerifyThreadAffinity();
OpenGL.glDrawElements(OpenGL.GL_TRIANGLES, numIndices, OpenGL.GL_UNSIGNED_INT, new IntPtr(offset));
OpenGL.CheckGLError();
}
public void Clear()
{
VerifyThreadAffinity();
OpenGL.glClearColor(0, 0, 0, 1);
OpenGL.CheckGLError();
OpenGL.glClear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT);
OpenGL.CheckGLError();
}
public void EnableDepthBuffer()
{
VerifyThreadAffinity();
OpenGL.glClear(OpenGL.GL_DEPTH_BUFFER_BIT);
OpenGL.CheckGLError();
OpenGL.glEnable(OpenGL.GL_DEPTH_TEST);
OpenGL.CheckGLError();
OpenGL.glDepthFunc(OpenGL.GL_LEQUAL);
OpenGL.CheckGLError();
}
public void DisableDepthBuffer()
{
VerifyThreadAffinity();
OpenGL.glDisable(OpenGL.GL_DEPTH_TEST);
OpenGL.CheckGLError();
}
public void ClearDepthBuffer()
{
VerifyThreadAffinity();
OpenGL.glClear(OpenGL.GL_DEPTH_BUFFER_BIT);
OpenGL.CheckGLError();
}
public void SetBlendMode(BlendMode mode)
{
VerifyThreadAffinity();
OpenGL.glBlendEquation(OpenGL.GL_FUNC_ADD);
OpenGL.CheckGLError();
switch (mode)
{
case BlendMode.None:
OpenGL.glDisable(OpenGL.GL_BLEND);
break;
case BlendMode.Alpha:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_ONE, OpenGL.GL_ONE_MINUS_SRC_ALPHA);
break;
case BlendMode.Additive:
case BlendMode.Subtractive:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_ONE, OpenGL.GL_ONE);
if (mode == BlendMode.Subtractive)
{
OpenGL.CheckGLError();
OpenGL.glBlendEquationSeparate(OpenGL.GL_FUNC_REVERSE_SUBTRACT, OpenGL.GL_FUNC_ADD);
}
break;
case BlendMode.Multiply:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_DST_COLOR, OpenGL.GL_ONE_MINUS_SRC_ALPHA);
OpenGL.CheckGLError();
break;
case BlendMode.Multiplicative:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_ZERO, OpenGL.GL_SRC_COLOR);
break;
case BlendMode.DoubleMultiplicative:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_DST_COLOR, OpenGL.GL_SRC_COLOR);
break;
case BlendMode.LowAdditive:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_DST_COLOR, OpenGL.GL_ONE);
break;
case BlendMode.Screen:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_SRC_COLOR, OpenGL.GL_ONE_MINUS_SRC_COLOR);
break;
case BlendMode.Translucent:
OpenGL.glEnable(OpenGL.GL_BLEND);
OpenGL.CheckGLError();
OpenGL.glBlendFunc(OpenGL.GL_DST_COLOR, OpenGL.GL_ONE_MINUS_DST_COLOR);
break;
}
OpenGL.CheckGLError();
}
public void SetVSyncEnabled(bool enabled)
{
VerifyThreadAffinity();
SDL.SDL_GL_SetSwapInterval(enabled ? 1 : 0);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
void Dispose(bool _)
{
if (context != IntPtr.Zero)
{
SDL.SDL_GL_DeleteContext(context);
context = IntPtr.Zero;
}
}
~Sdl2GraphicsContext()
{
Dispose(false);
}
}
}