Real-time Gradient Estimating in Texture-Based Volume Rendering
基于实时梯度计算的快速纹理映射体绘制

A novel technique for texture-based volume rendering is discussed,which estimates and normalizes the gradient on the fly.During rendering the gradient is calculated on each voxel,and normalized for the lighting computation.The new technique is presented to load the volume dataset to the 3D texture directly without the time consumptive process to pre-compute the gradient,and circumvent the huge memory consumption in previous approaches.Additionally,the 3D Sobel gradient operator is applied to the gradient estimation,which improves the quality of the rendering.The sophisticated PC graphics hardware functionality is utilized,especially the fragment program,to implement the gradient estimation.Several examples are given to illustrate the effectiveness on real clinic 3D CT datasets.