stgsharp/StgSharp.Common/Graphics/OpenGL/glRenderStream.cs

//-----------------------------------------------------------------------
// -----------------------------------------------------------------------
// file="glRenderStream.cs"
// Project: StgSharp
// AuthorGroup: Nitload Space
// Copyright (c) Nitload Space. All rights reserved.
//     
// Permission is hereby granted, free of charge, to any person 
// obtaining a copy of this software and associated documentation 
// files (the “Software”), to deal in the Software without restriction, 
// including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, 
// and to permit persons to whom the Software is furnished to do so, 
// subject to the following conditions:
//     
// The above copyright notice and 
// this permission notice shall be included in all copies 
// or substantial portions of the Software.
//     
// THE SOFTWARE IS PROVIDED “AS IS”, 
// WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
// ARISING FROM, OUT OF OR IN CONNECTION WITH 
// THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//     
// -----------------------------------------------------------------------
// -----------------------------------------------------------------------
using StgSharp.Mathematics;
using StgSharp.Threading;

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace StgSharp.Graphics.OpenGL
{
    public abstract partial class glRender : RenderStream
    {

        private protected static readonly ConcurrentDictionary<glRender, Thread> renderToThread
            = new ConcurrentDictionary<glRender, Thread>();

        private OpenGLFunction _context;

        protected internal OpenGLFunction GL
        {
            get { return _context; }
        }

        /// <summary>
        ///   Initialize an opengl context and load all opengl functions.
        /// </summary>
        public unsafe void InitializeContext()
        {
            if (ContextHandle == default)
            {
                ContextHandle = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(OpenglContext)));
                OpenglContext* contextID = (OpenglContext*)ContextHandle;
                contextID->glGetString = (delegate*<uint, IntPtr>)IntPtr.Zero;
            }
            if (GL == null) {
                _context = OpenGLFunction.BuildGlFunctionPackage(ContextHandle);
            }
        }

        /// <summary>
        ///   Initialize an OpenGl viewPortDisplay if current form has not been binded to any
        ///   viewPortDisplay.  and set the viewPortDisplay binded to current form as current OpenGL
        ///   viewPortDisplay.
        /// </summary>
        /// <exception cref="Exception">
        ///   Something goes wrong and World fails in creating a new OpenGL viewPortDisplay.
        /// </exception>
        public unsafe void MakeAsCurrentContext()
        {
            InternalIO.glfwMakeContextCurrent(CanvasHandle);
            OpenGLFunction.CurrentGL = this.GL;
        }

        /// <inheritdoc />
        public override void RenderEnd()
        {
            if (!renderToThread.TryGetValue(this, out Thread t) || t != Thread.CurrentThread) {
                throw new InvalidOperationException(
                    $"Current render has had been binded to thread {t!.ManagedThreadId}");
            }
            SwapBuffers();
            renderToThread[this] = ThreadHelper.EmptyThread;
            InternalIO.glfwMakeContextCurrent(IntPtr.Zero);
            OpenGLFunction.CurrentGL = null;
        }

        /// <inheritdoc />
        public override void RenderStart()
        {
            Thread current = Thread.CurrentThread;
            if (!renderToThread.TryGetValue(this, out Thread t) || t == ThreadHelper.EmptyThread)
            {
                renderToThread[this] = current;
                MakeAsCurrentContext();
                return;
            }
            if (t != current) {
                throw new InvalidOperationException(
                    $"Current render has had been binded to thread {t!.ManagedThreadId}");
            }
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override void SetSizeLimit(int minWidth, int minHeight, int maxWidth, int maxHeight)
        {
            InternalIO.glfwSetWindowSizeLimits(
                this.CanvasHandle, minWidth, minHeight, maxWidth, maxHeight);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal sealed override void PlatformSpecifiedInitialize()
        {
            InitializeContext();
            MakeAsCurrentContext();
            glManager.LoadOpenGLApiTo(BindedViewPortContext.GraphicHandle);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal sealed override void Terminate()
        {
            CustomizeDeinit();
        }

        protected sealed override Uniform<Matrix44> NativeCameraUniform(
                                                    ShaderProgram source,
                                                    string name)
        {
            NativeCamera.GainAllUniforms(source, name);
            return NativeCamera.convertedUniform;
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        protected sealed override void NativeCameraViewRange(
                                       Radius fieldOfRange,
                                       Vec2 offset,
                                       (float frontDepth, float backDepth) viewDepth)
        {
            NativeCamera.SetViewRange(fieldOfRange, this.Size, offset, viewDepth);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        protected sealed override void NativeCameraViewTarget(
                                       Vec3 position,
                                       Vec3 direction,
                                       Vec3 up)
        {
            NativeCamera.SetViewDirection(position, direction, up);
        }

        #region Key Control

        protected KeyStatus CheckKey(KeyboardKey key)
        {
            return InternalIO.glfwGetKey(this.CanvasHandle, (int)key);
        }

        protected KeyStatus CheckKey(Mouse key)
        {
            return InternalIO.glfwGetKey(this.CanvasHandle, (int)key);
        }

        protected KeyStatus CheckKey(Joystick key)
        {
            return InternalIO.glfwGetKey(this.CanvasHandle, (int)key);
        }

        #endregion
    }
}