公开(公告)号：US5835097A

公开(公告)日：1998-11-10

申请号：US774787

申请日：1996-12-30

申请人： Gautam P. Vaswani ,  Michael Larson ,  Tom Dye

发明人： Gautam P. Vaswani ,  Michael Larson ,  Tom Dye

IPC分类号： G06T15/04 ,  G06F15/00

CPC分类号： G06T15/04

摘要： In a computer system having a host processor, a peripheral graphics device, a display screen, and a memory, a non-homogenous second order perspective texture mapping process. Polygon coordinates, a.sub.m,n, defining a texture polygon, are received. Initial values are received for a set of parameters including u.sub.main, v.sub.main, dv.sub.ortho, dv.sub.main, du.sub.ortho, du.sub.main, d.sup.2 u.sub.ortho, d.sup.2 u.sub.main, d.sup.2 v.sub.ortho, d.sup.2 v.sub.main, du.sub.ortho-ADD, and dv.sub.ortho-ADD. The texture polygon includes span regions. A span value, j, is set to an initial value to designate an initial span region of the texture polygon in (m, n) polygon coordinate space. The total number of rows, n.sub.max, is determined for the current span region of the polygon. The total number of polygon coordinates, m.sub.max, in the current row, n, of the texture polygon is determined. An (x, y) display coordinate, corresponding to the current polygon coordinate, a.sub.m,n, is set by translating from (m, n) polygon space to (x, y) display coordinate space. Texture coordinates, u(a.sub.m,n) and v(a.sub.m,n), are determined, according to the present invention, for each polygon coordinate, a.sub.m,n, using linear interpolation based on a set of relationships that utilize the above parameters without using a repetitive divide operation. A display pixel of a color determined according to texture coordinates, u(a.sub.m,n) and v(a.sub.m,n), is rendered on a display screen at the determined (x, y) position.

摘要翻译： 在具有主机处理器，外围图形设备，显示屏幕和存储器的计算机系统中，非均匀的二阶透视纹理映射处理。 接收定义纹理多边形的多边形坐标，am，n。 初始值接收到一组参数，包括umain，vmain，dvortho，dvmain，duortho，dumain，d2uortho，d2umain，d2vortho，d2vmain，duortho-ADD和dvortho-ADD。 纹理多边形包括跨度区域。 跨度值j被设置为初始值以指定（m，n）多边形坐标空间中的纹理多边形的初始跨度区域。 为多边形的当前跨度区域确定总行数nmax。 确定纹理多边形的当前行n中的多边形坐标的总数，mmax。 通过从（m，n）多边形空间转换为（x，y）显示坐标空间来设置与当前多边形坐标am，n对应的（x，y）显示坐标。 根据本发明，根据本发明确定纹理坐标u（am，n）和v（am，n），对于每个多边形坐标am，n，使用基于利用上述参数的一组关系的线性插值而没有 使用重复划分操作。 根据纹理坐标u（am，n）和v（am，n）确定的颜色的显示像素在确定的（x，y）位置的显示屏幕上呈现。