83 void rt_heightfield(void *tex, vector ctr, int m, int n, apiflt *field, apiflt wx, apiflt wy) {  in rt_heightfield()  argument
93         for (xx = 0; xx < (m - 1); xx++) {  in rt_heightfield()
94             v0.x = wx * (xx) / (m * 1.0) + xoff;  in rt_heightfield()
95             v0.y = field[(yy)*m + (xx)] + zoff;  in rt_heightfield()
98             v1.x = wx * (xx + 1) / (m * 1.0) + xoff;  in rt_heightfield()
99             v1.y = field[(yy)*m + (xx + 1)] + zoff;  in rt_heightfield()
102             v2.x = wx * (xx + 1) / (m * 1.0) + xoff;  in rt_heightfield()
103             v2.y = field[(yy + 1) * m + (xx + 1)] + zoff;  in rt_heightfield()
108             v0.x = wx * (xx) / (m * 1.0) + xoff;  in rt_heightfield()
109             v0.y = field[(yy)*m + (xx)] + zoff;  in rt_heightfield()
112             v1.x = wx * (xx) / (m * 1.0) + xoff;  in rt_heightfield()
113             v1.y = field[(yy + 1) * m + (xx)] + zoff;  in rt_heightfield()
116             v2.x = wx * (xx + 1) / (m * 1.0) + xoff;  in rt_heightfield()
117             v2.y = field[(yy + 1) * m + (xx + 1)] + zoff;  in rt_heightfield()
126 rt_sheightfield(void *tex, vector ctr, int m, int n, apiflt *field, apiflt wx, apiflt wy) {  in rt_sheightfield()  argument
133     vertices = (vector *)malloc(m * n * sizeof(vector));  in rt_sheightfield()
134     normals = (vector *)malloc(m * n * sizeof(vector));  in rt_sheightfield()
140     xinc = wx / ((apiflt)m);  in rt_sheightfield()
145         for (x = 0; x < m; x++) {  in rt_sheightfield()
146             addr = y * m + x;  in rt_sheightfield()
153     for (x = 1; x < m; x++) {  in rt_sheightfield()
154         normals[x] = normals[(n - 1) * m + x] = rt_vector(0.0, 1.0, 0.0);  in rt_sheightfield()
157         normals[y * m] = normals[y * m + (m - 1)] = rt_vector(0.0, 1.0, 0.0);  in rt_sheightfield()
160         for (x = 1; x < (m - 1); x++) {  in rt_sheightfield()
161             addr = y * m + x;  in rt_sheightfield()
165                                       -(field[addr + m] - field[addr - m]) / (2.0 * yinc));  in rt_sheightfield()
173         for (x = 0; x < (m - 1); x++) {  in rt_sheightfield()
174             addr = y * m + x;  in rt_sheightfield()
178                     vertices[addr + 1 + m],  in rt_sheightfield()
181                     normals[addr + 1 + m],  in rt_sheightfield()
185                     vertices[addr + m],  in rt_sheightfield()
186                     vertices[addr + 1 + m],  in rt_sheightfield()
188                     normals[addr + m],  in rt_sheightfield()
189                     normals[addr + 1 + m]);  in rt_sheightfield()
252 void rt_landscape(void *tex, int m, int n, vector ctr, apiflt wx, apiflt wy) {  in rt_landscape()  argument
256     totalsize = m * n;  in rt_landscape()
263         for (x = 0; x < m; x++) {  in rt_landscape()
264             field[x + y * m] = 0.0;  in rt_landscape()
269     field[m - 1] = 1.0 + (rand() % 100) / 100.0;  in rt_landscape()
270     field[0 + m * (n - 1)] = 1.0 + (rand() % 100) / 100.0;  in rt_landscape()
271     field[m - 1 + m * (n - 1)] = 1.0 + (rand() % 100) / 100.0;  in rt_landscape()
273     subdivide(field, m, n, wx, wy, 0, 0, m - 1, n - 1);  in rt_landscape()
275     rt_sheightfield(tex, ctr, m, n, field, wx, wy);  in rt_landscape()