C# OpenGL.BindVertexArray方法代码示例

        void IRenderable.Render(OpenGL gl, RenderMode renderMode)
        {
            if (positionBuffer != null && colorBuffer != null && radiusBuffer != null)
            {
                if (this.shaderProgram == null)
                {
                    this.shaderProgram = InitShader(gl, renderMode);
                }
                if (this.vertexArrayObject == null)
                {
                    CreateVertexArrayObject(gl, renderMode);
                }

                BeforeRendering(gl, renderMode);

                if (this.RenderGrid && this.vertexArrayObject != null)
                {
                    gl.Enable(OpenGL.GL_BLEND);
                    gl.BlendFunc(SharpGL.Enumerations.BlendingSourceFactor.SourceAlpha, SharpGL.Enumerations.BlendingDestinationFactor.OneMinusSourceAlpha);

                    gl.BindVertexArray(this.vertexArrayObject[0]);
                    gl.DrawArrays(OpenGL.GL_POINTS, 0, count);
                    gl.BindVertexArray(0);

                    gl.Disable(OpenGL.GL_BLEND);
                }

                AfterRendering(gl, renderMode);
            }
        }

        public BackgroundRenderer(OpenGL gl)
        {
            _gl = gl;

            _program = new BackgroundShader(gl);
            _flat = new VAO(gl);
            _flatBuffer = new VBO(gl);

            using (new Bind(_flat))
            using (new Bind(_flatBuffer))
            {
                var flatData = new float[] { -1, -1, 1, -1, -1, 1, 1, 1, };
                _flatBuffer.Update(flatData, flatData.Length * sizeof(float));
                gl.EnableVertexAttribArray(0);
                gl.VertexAttribPointer(0, 2, OpenGL.GL_FLOAT, false, 0, new IntPtr(0));
                gl.BindVertexArray(0);
            }
        }

        public PostProcesser(OpenGL gl,int width,int height)
        {
            _gl = gl;
            _fbo = new FBO(gl, width, height);

            _flatProgram = new FlatShader(gl);

            _flat = new VAO(gl);
            _flatBuffer = new VBO(gl);

            using (new Bind(_flat))
            using (new Bind(_flatBuffer))
            {
                var flatData = new float[] { -1, -1, 1, -1, -1, 1, 1, 1, };
                _flatBuffer.Update(flatData, flatData.Length * sizeof(float));
                gl.EnableVertexAttribArray(0);
                gl.VertexAttribPointer(0, 2, OpenGL.GL_FLOAT, false, 0, new IntPtr(0));
                gl.BindVertexArray(0);
            }
        }

        public OctreeRenderer(OctreeModel model, OpenGL gl)
        {
            _gl = gl;
            _octreeProgram = new OctreeShader(gl);
            _cubes = new VAO(gl);
            _cubeBuffer = new VBO(gl);

            var filled = model.Node.Flatten().Where(o => o.State == NodeState.Filled).ToArray();
            _count = filled.Length;
            var list = new List<float>();
            foreach (var octreeNode in filled)
            {
                list.AddRange(octreeNode.Center.ToArray().Select(d => (float)d));

                list.AddRange(new[]
                        {
                            (float)MathsHelper.Map(octreeNode.Color.R, 0, 255, 0, 1),
                            (float)MathsHelper.Map(octreeNode.Color.G, 0, 255, 0, 1),
                            (float)MathsHelper.Map(octreeNode.Color.B, 0, 255, 0, 1),
                            (float)MathsHelper.Map(octreeNode.Color.A, 0, 255, 0, 1),
                            (float)octreeNode.Size
                        });
            }

            var vertices = list.ToArray();

            using (new Bind(_cubes))
            using (new Bind(_cubeBuffer))
            {
                _cubeBuffer.Update(vertices, vertices.Length * sizeof(float));
                const int stride = sizeof(float) * 8;
                gl.EnableVertexAttribArray(0);
                gl.VertexAttribPointer(0, 3, OpenGL.GL_FLOAT, false, stride, new IntPtr(0));

                gl.EnableVertexAttribArray(1);
                gl.VertexAttribPointer(1, 4, OpenGL.GL_FLOAT, false, stride, new IntPtr(sizeof(float) * 3));

                gl.EnableVertexAttribArray(2);

                gl.VertexAttribPointer(2, 1, OpenGL.GL_FLOAT, false, stride, new IntPtr(sizeof(float) * 7));
                gl.BindVertexArray(0);
            }
        }

        void IRenderable.Render(OpenGL gl, RenderMode renderMode)
        {
            if (positionBuffer == null || colorBuffer == null) { return; }

            if (this.shaderProgram == null)
            {
                this.shaderProgram = InitShader(gl, renderMode);
            }
            if (this.vertexArrayObject == null)
            {
                CreateVertexArrayObject(gl, renderMode);
            }

            BeforeRendering(gl, renderMode);

            if (this.RenderGridWireframe && this.vertexArrayObject != null)
            {
                //if (wireframeIndexBuffer != null)
                if (positionBuffer != null && colorBuffer != null && indexBuffer != null)
                {
                    shaderProgram.SetUniform1(gl, "renderingWireframe", 1.0f);// shader一律上白色。

                    gl.Disable(OpenGL.GL_LINE_STIPPLE);
                    gl.Disable(OpenGL.GL_POLYGON_STIPPLE);
                    gl.Enable(OpenGL.GL_LINE_SMOOTH);
                    gl.Enable(OpenGL.GL_POLYGON_SMOOTH);
                    gl.ShadeModel(SharpGL.Enumerations.ShadeModel.Smooth);
                    gl.Hint(SharpGL.Enumerations.HintTarget.LineSmooth, SharpGL.Enumerations.HintMode.Nicest);
                    gl.Hint(SharpGL.Enumerations.HintTarget.PolygonSmooth, SharpGL.Enumerations.HintMode.Nicest);
                    gl.PolygonMode(SharpGL.Enumerations.FaceMode.FrontAndBack, SharpGL.Enumerations.PolygonMode.Lines);

                    gl.Enable(OpenGL.GL_PRIMITIVE_RESTART);
                    gl.PrimitiveRestartIndex(uint.MaxValue);

                    gl.Enable(OpenGL.GL_BLEND);
                    gl.BlendFunc(SharpGL.Enumerations.BlendingSourceFactor.SourceAlpha, SharpGL.Enumerations.BlendingDestinationFactor.OneMinusSourceAlpha);

                    gl.BindVertexArray(this.vertexArrayObject[0]);
                    gl.BindBuffer(OpenGL.GL_ELEMENT_ARRAY_BUFFER, indexBuffer[0]);
                    gl.DrawElements(OpenGL.GL_QUAD_STRIP, this.indexBufferLength, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                    gl.BindVertexArray(0);

                    gl.Disable(OpenGL.GL_BLEND);

                    gl.Disable(OpenGL.GL_PRIMITIVE_RESTART);

                    gl.PolygonMode(SharpGL.Enumerations.FaceMode.FrontAndBack, SharpGL.Enumerations.PolygonMode.Filled);
                    gl.Disable(OpenGL.GL_POLYGON_SMOOTH);
                }
            }

            if (this.RenderGrid && this.vertexArrayObject != null)
            {
                if (positionBuffer != null && colorBuffer != null && indexBuffer != null)
                {
                    shaderProgram.SetUniform1(gl, "renderingWireframe", 0.0f);// shader根据uv buffer来上色。

                    gl.Enable(OpenGL.GL_PRIMITIVE_RESTART);
                    gl.PrimitiveRestartIndex(uint.MaxValue);

                    gl.Enable(OpenGL.GL_BLEND);
                    gl.BlendFunc(SharpGL.Enumerations.BlendingSourceFactor.SourceAlpha, SharpGL.Enumerations.BlendingDestinationFactor.OneMinusSourceAlpha);

                    gl.BindVertexArray(this.vertexArrayObject[0]);
                    gl.BindBuffer(OpenGL.GL_ELEMENT_ARRAY_BUFFER, indexBuffer[0]);
                    gl.DrawElements(OpenGL.GL_QUAD_STRIP, this.indexBufferLength, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                    gl.BindVertexArray(0);

                    gl.Disable(OpenGL.GL_BLEND);

                    gl.Disable(OpenGL.GL_PRIMITIVE_RESTART);
                }
            }

            AfterRendering(gl, renderMode);
        }

        private void CreateVertexArrayObject(OpenGL gl, RenderMode renderMode)
        {
            if (this.positionBuffer == null || this.colorBuffer == null) { return; }

            this.vertexArrayObject = new uint[1];
            gl.GenVertexArrays(1, this.vertexArrayObject);
            gl.BindVertexArray(this.vertexArrayObject[0]);

            // prepare positions
            {
                int location = shaderProgram.GetAttributeLocation(gl, in_Position);
                ATTRIB_INDEX_POSITION = (uint)location;
                gl.BindBuffer(OpenGL.GL_ARRAY_BUFFER, positionBuffer[0]);
                gl.VertexAttribPointer(ATTRIB_INDEX_POSITION, 3, OpenGL.GL_FLOAT, false, 0, IntPtr.Zero);
                gl.EnableVertexAttribArray(ATTRIB_INDEX_POSITION);
            }
            // prepare colors
            {
                int location = shaderProgram.GetAttributeLocation(gl, in_uv);
                ATTRIB_INDEX_UV = (uint)location;
                gl.BindBuffer(OpenGL.GL_ARRAY_BUFFER, colorBuffer[0]);
                gl.VertexAttribPointer(ATTRIB_INDEX_UV, 1, OpenGL.GL_FLOAT, false, 0, IntPtr.Zero);
                gl.EnableVertexAttribArray(ATTRIB_INDEX_UV);
            }

            gl.BindVertexArray(0);
        }

 public void BindHTVAO(OpenGL gl)
 {
     gl.BindVertexArray(VaoHT);
 }

        public void PrepareNMVAO(OpenGL gl, NormalMaterialProgram program)
        {
            var vertArrIds = new uint[1];
            gl.GenVertexArrays(1, vertArrIds);

            VaoNM = vertArrIds[0];
            gl.BindVertexArray(VaoNM);

            BindNMVBOs(gl, program);

            gl.EnableVertexAttribArray(0);
            gl.BindVertexArray(0);
        }

        public void PrepareHTVAO(OpenGL gl, HitTestProgram program)
        {
            var vertArrIds = new uint[1];
            gl.GenVertexArrays(1, vertArrIds);

            VaoHT = vertArrIds[0];
            gl.BindVertexArray(VaoHT);

            BindHTVBOs(gl, program);

            gl.EnableVertexAttribArray(0);
            gl.BindVertexArray(0);
        }

 public void BindNMVAO(OpenGL gl)
 {
     gl.BindVertexArray(VaoNM);
 }

        private void runGlThread(object args)
        {
            var inputs = (Tuple<CancellationToken>) args;

            var cancelToken = inputs.Item1;
            var gl = new OpenGL();

            int localRenderWidth = 1;
            int localRenderHeight = 1;
            if (!createRenderContext(gl, localRenderWidth, localRenderHeight))
            {
            //TODO better error handling here
            Console.WriteLine("*** Unable to create OpenGL Render Context");
            return;
            }

            uint activeVaoHandle;
            uint activeGlProgramHandle;
            initGLObjects(gl, out activeVaoHandle, out activeGlProgramHandle);

            ActiveProgramValues localActiveProgramValues = null;
            while (!cancelToken.IsCancellationRequested)
            {
            bool resizeRenderContext;
            lock (this)
            {
                if (!ReferenceEquals(localActiveProgramValues, activeProgramValues))
                {
                    localActiveProgramValues = activeProgramValues;
                    if (localActiveProgramValues.Valid)
                    {
                        linkProgram(gl, localActiveProgramValues, activeGlProgramHandle);
                    } else
                    {
                        // Leave the old program running. This prevents the user from seeing
                        // a black screen while they are in the process of modifying a shader.
                    }
                }

                resizeRenderContext = localRenderWidth != renderWidth || localRenderHeight != renderHeight;
                localRenderWidth = renderWidth;
                localRenderHeight = renderHeight;
            }

            if (resizeRenderContext)
            {
                localActiveProgramValues = null;
                deleteGlObjects(gl, activeVaoHandle, activeGlProgramHandle);
                if (!createRenderContext(gl, localRenderWidth, localRenderHeight))
                {
            //TODO better error handling here
                    Console.WriteLine("*** Unable to resize OpenGL Render Context");
                    return;
                }
                initGLObjects(gl, out activeVaoHandle, out activeGlProgramHandle);
            }

            gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT);
            gl.BindVertexArray(activeVaoHandle);
            gl.UseProgram(activeGlProgramHandle);
            gl.DrawArrays(OpenGL.GL_TRIANGLES, 0, 3);

            // do some other stuff while the image is rendering, to give it a chance to finish
            ShaderCompiler.ValidateShaders(gl);

            var provider = gl.RenderContextProvider as FBORenderContextProvider;
            Debug.Assert(provider != null, "Render context provider is not an FBO renderer");
            //TODO this call to blit will probably block. Find a better way to copy the image to CPU memory.
            gl.Blit(IntPtr.Zero);
            var hBitmap = provider.InternalDIBSection.HBitmap;

            if (hBitmap != IntPtr.Zero)
            {
                var bitmap = GetFormattedBitmapSource(hBitmap);
                // the bitmap needs to be frozen in order to share it between threads
                bitmap.Freeze();
                ImageRendered(bitmap);
            }
            }

            deleteGlObjects(gl, activeVaoHandle, activeGlProgramHandle);
        }

        public void BindAll(OpenGL gl)
        {
            UseProgram(gl, () =>
            {
                // Update uniforms.
                foreach (var action in ChangedUniforms)
                {
                    action.Invoke(gl);
                }
                ChangedUniforms.Clear();

                foreach (var group in BufferGroups)
                {
                    group.BindVAO(gl);
                    gl.DrawElements(OpenGL.GL_TRIANGLES, group.IndicesCount, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                    gl.BindVertexArray(0);
                }
            });
        }

        public void PrepareVAO(OpenGL gl, LinesProgram program)
        {
            var vertArrIds = new uint[1];
            gl.GenVertexArrays(1, vertArrIds);

            Vao = vertArrIds[0];
            gl.BindVertexArray(Vao);

            BindVBOs(gl, program);

            gl.EnableVertexAttribArray(0);
            gl.BindVertexArray(0);
        }

        public void BindVAO(OpenGL gl)
        {
            var isBuffer = new bool[]
            {
                gl.IsBuffer(Vao),
                gl.IsBuffer(Ibo),
                gl.IsBuffer(Position),
                gl.IsBuffer(Normal),
                gl.IsBuffer(Vao),
                gl.IsBuffer(Vao),
                gl.IsBuffer(Vao),
                gl.IsBuffer(Vao),
            };

            gl.BindVertexArray(Vao);
        }

        /// <summary>
        /// 渲染基质
        /// </summary>
        /// <param name="gl"></param>
        /// <param name="renderMode"></param>
        private void DoRenderMatrix(OpenGL gl, RenderMode renderMode)
        {
            if (this.positionBuffer == null || this.colorBuffer == null) { return; }

            if (this.RenderGrid && this.matrixVertexArrayObject != null)
            {
                shaderProgram.SetUniform1(gl, "renderingWireframe", 0.0f);
                shaderProgram.SetUniform1(gl, "opacity", this.Opacity);

                gl.Enable(OpenGL.GL_POLYGON_OFFSET_FILL);
                gl.PolygonOffset(1.0f, 1.0f);

                gl.Enable(OpenGL.GL_BLEND);
                gl.BlendFunc(SharpGL.Enumerations.BlendingSourceFactor.SourceAlpha, SharpGL.Enumerations.BlendingDestinationFactor.OneMinusSourceAlpha);

                gl.BindVertexArray(matrixVertexArrayObject[0]);

                switch (this.MatrixType)
                {
                    case MatrixFormat.Triangle:
                        gl.DrawArrays(this.matrixRenderMode, 0, this.MatrixVertexOrIndexCount);
                        break;
                    case MatrixFormat.Tetrahedron:
                        gl.Enable(OpenGL.GL_PRIMITIVE_RESTART);
                        gl.PrimitiveRestartIndex(uint.MaxValue);

                        gl.BindBuffer(OpenGL.GL_ELEMENT_ARRAY_BUFFER, this.matrixIndexBuffer[0]);
                        gl.DrawElements(this.matrixRenderMode, this.MatrixVertexOrIndexCount, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                        gl.Disable(OpenGL.GL_PRIMITIVE_RESTART);
                        break;
                    case MatrixFormat.TriangularPrism:
                        // 先渲染三棱柱的上下三角形
                        gl.DrawArrays(OpenGL.GL_TRIANGLES, 0, this.MatrixVertexOrIndexCount);
                        // 再渲染三棱柱的三个侧面
                        gl.Enable(OpenGL.GL_PRIMITIVE_RESTART);
                        gl.PrimitiveRestartIndex(uint.MaxValue);
                        gl.BindBuffer(OpenGL.GL_ELEMENT_ARRAY_BUFFER, this.matrixIndexBuffer[0]);
                        gl.DrawElements(this.matrixRenderMode, this.MatrixVertexOrIndexCount, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                        gl.Disable(OpenGL.GL_PRIMITIVE_RESTART);
                        break;
                    default:
                        break;
                }
                gl.BindVertexArray(0);
                gl.Disable(OpenGL.GL_BLEND);

                gl.Disable(OpenGL.GL_POLYGON_OFFSET_FILL);
            }

            if (this.RenderGridWireframe && this.matrixVertexArrayObject != null)
            {
                shaderProgram.SetUniform1(gl, "renderingWireframe", 1.0f);
                shaderProgram.SetUniform1(gl, "opacity", this.Opacity);
                gl.PolygonMode(SharpGL.Enumerations.FaceMode.FrontAndBack, SharpGL.Enumerations.PolygonMode.Lines);

                gl.Enable(OpenGL.GL_BLEND);
                gl.BlendFunc(SharpGL.Enumerations.BlendingSourceFactor.SourceAlpha, SharpGL.Enumerations.BlendingDestinationFactor.OneMinusSourceAlpha);

                gl.BindVertexArray(matrixVertexArrayObject[0]);
                switch (this.MatrixType)
                {
                    case MatrixFormat.Triangle:
                        gl.DrawArrays(this.matrixRenderMode, 0, this.MatrixVertexOrIndexCount);
                        break;
                    case MatrixFormat.Tetrahedron:
                        gl.Enable(OpenGL.GL_PRIMITIVE_RESTART);
                        gl.PrimitiveRestartIndex(uint.MaxValue);
                        gl.BindBuffer(OpenGL.GL_ELEMENT_ARRAY_BUFFER, this.matrixIndexBuffer[0]);
                        gl.DrawElements(this.matrixRenderMode, this.MatrixVertexOrIndexCount, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                        gl.Disable(OpenGL.GL_PRIMITIVE_RESTART);
                        break;
                    case MatrixFormat.TriangularPrism:
                        // 先渲染三棱柱的上下三角形
                        gl.DrawArrays(OpenGL.GL_TRIANGLES, 0, this.MatrixVertexOrIndexCount / 9 * 6);
                        // 再渲染三棱柱的三个侧面
                        gl.Enable(OpenGL.GL_PRIMITIVE_RESTART);
                        gl.PrimitiveRestartIndex(uint.MaxValue);
                        gl.BindBuffer(OpenGL.GL_ELEMENT_ARRAY_BUFFER, this.matrixIndexBuffer[0]);
                        gl.DrawElements(this.matrixRenderMode, this.MatrixVertexOrIndexCount, OpenGL.GL_UNSIGNED_INT, IntPtr.Zero);
                        gl.Disable(OpenGL.GL_PRIMITIVE_RESTART);
                        break;
                    default:
                        break;
                }
                gl.PolygonMode(SharpGL.Enumerations.FaceMode.FrontAndBack, SharpGL.Enumerations.PolygonMode.Filled);
                gl.BindVertexArray(0);

                gl.Disable(OpenGL.GL_BLEND);
            }
        }