private RenderModel LoadRenderModel()

in Assets/MRTK/Providers/OpenVR/OpenVRRenderModel.cs [235:380]
121 lines of code
18 McCabe index (conditional complexity)

        private RenderModel LoadRenderModel(CVRRenderModels renderModels, string renderModelName, string baseName)
        {
            var pRenderModel = System.IntPtr.Zero;

            EVRRenderModelError error;
            while (true)
            {
                error = renderModels.LoadRenderModel_Async(renderModelName, ref pRenderModel);
                if (error != EVRRenderModelError.Loading)
                    break;

                Sleep();
            }

            if (error != EVRRenderModelError.None)
            {
                Debug.LogError(string.Format("Failed to load render model {0} - {1}", renderModelName, error.ToString()));
                return null;
            }

            var renderModel = MarshalRenderModel(pRenderModel);

            var vertices = new Vector3[renderModel.unVertexCount];
            var normals = new Vector3[renderModel.unVertexCount];
            var uv = new Vector2[renderModel.unVertexCount];

            var type = typeof(RenderModel_Vertex_t);
            for (int iVert = 0; iVert < renderModel.unVertexCount; iVert++)
            {
                var ptr = new System.IntPtr(renderModel.rVertexData.ToInt64() + iVert * Marshal.SizeOf(type));
                var vert = (RenderModel_Vertex_t)Marshal.PtrToStructure(ptr, type);

                vertices[iVert] = new Vector3(vert.vPosition.v0, vert.vPosition.v1, -vert.vPosition.v2);
                normals[iVert] = new Vector3(vert.vNormal.v0, vert.vNormal.v1, -vert.vNormal.v2);
                uv[iVert] = new Vector2(vert.rfTextureCoord0, vert.rfTextureCoord1);
            }

            int indexCount = (int)renderModel.unTriangleCount * 3;
            var indices = new short[indexCount];
            Marshal.Copy(renderModel.rIndexData, indices, 0, indices.Length);

            var triangles = new int[indexCount];
            for (int iTri = 0; iTri < renderModel.unTriangleCount; iTri++)
            {
                triangles[iTri * 3 + 0] = (int)indices[iTri * 3 + 2];
                triangles[iTri * 3 + 1] = (int)indices[iTri * 3 + 1];
                triangles[iTri * 3 + 2] = (int)indices[iTri * 3 + 0];
            }

            var mesh = new Mesh
            {
                vertices = vertices,
                normals = normals,
                uv = uv,
                triangles = triangles
            };

            // Check cache before loading texture.
            var material = Materials[renderModel.diffuseTextureId] as Material;
            if (material == null || material.mainTexture == null)
            {
                var pDiffuseTexture = System.IntPtr.Zero;

                while (true)
                {
                    error = renderModels.LoadTexture_Async(renderModel.diffuseTextureId, ref pDiffuseTexture);
                    if (error != EVRRenderModelError.Loading)
                    {
                        break;
                    }

                    Sleep();
                }

                if (error == EVRRenderModelError.None)
                {
                    var diffuseTexture = MarshalRenderModel_TextureMap(pDiffuseTexture);
                    var texture = new Texture2D(diffuseTexture.unWidth, diffuseTexture.unHeight, TextureFormat.RGBA32, false);
                    if (SystemInfo.graphicsDeviceType == UnityEngine.Rendering.GraphicsDeviceType.Direct3D11)
                    {
                        texture.Apply();
                        System.IntPtr texturePointer = texture.GetNativeTexturePtr();
                        while (true)
                        {
                            error = renderModels.LoadIntoTextureD3D11_Async(renderModel.diffuseTextureId, texturePointer);
                            if (error != EVRRenderModelError.Loading)
                            {
                                break;
                            }

                            Sleep();
                        }
                    }
                    else
                    {
                        var textureMapData = new byte[diffuseTexture.unWidth * diffuseTexture.unHeight * 4]; // RGBA
                        Marshal.Copy(diffuseTexture.rubTextureMapData, textureMapData, 0, textureMapData.Length);

                        var colors = new Color32[diffuseTexture.unWidth * diffuseTexture.unHeight];
                        int iColor = 0;
                        for (int iHeight = 0; iHeight < diffuseTexture.unHeight; iHeight++)
                        {
                            for (int iWidth = 0; iWidth < diffuseTexture.unWidth; iWidth++)
                            {
                                var r = textureMapData[iColor++];
                                var g = textureMapData[iColor++];
                                var b = textureMapData[iColor++];
                                var a = textureMapData[iColor++];
                                colors[iHeight * diffuseTexture.unWidth + iWidth] = new Color32(r, g, b, a);
                            }
                        }

                        texture.SetPixels32(colors);
                        texture.Apply();
                    }

                    material = new Material(shader != null ? shader : Shader.Find("Mixed Reality Toolkit/Standard"))
                    {
                        mainTexture = texture
                    };

                    Materials[renderModel.diffuseTextureId] = material;

                    renderModels.FreeTexture(pDiffuseTexture);
                }
                else
                {
                    Debug.Log("Failed to load render model texture for render model " + renderModelName + ". Error: " + error.ToString());
                }
            }

            // Delay freeing when we can since we'll often get multiple requests for the same model right
            // after another (e.g. two controllers or two base stations).
#if UNITY_EDITOR
            if (!Application.isPlaying)
            {
                renderModels.FreeRenderModel(pRenderModel);
            }
            else
#endif
            {
                StartCoroutine(FreeRenderModel(pRenderModel));
            }

            return new RenderModel(mesh, material);
        }