#include "glheader.h"
#include "config.h"
#include "m_eval.h"
static GLfloat inv_tab[MAX_EVAL_ORDER];
void
_math_horner_bezier_curve(const GLfloat * cp, GLfloat * out, GLfloat t,
GLuint dim, GLuint order)
{
GLfloat s, powert, bincoeff;
GLuint i, k;
if (order >= 2) {
bincoeff = (GLfloat) (order - 1);
s = 1.0F - t;
for (k = 0; k < dim; k++)
out[k] = s * cp[k] + bincoeff * t * cp[dim + k];
for (i = 2, cp += 2 * dim, powert = t * t; i < order;
i++, powert *= t, cp += dim) {
bincoeff *= (GLfloat) (order - i);
bincoeff *= inv_tab[i];
for (k = 0; k < dim; k++)
out[k] = s * out[k] + bincoeff * powert * cp[k];
}
}
else {
for (k = 0; k < dim; k++)
out[k] = cp[k];
}
}
void
_math_horner_bezier_surf(GLfloat * cn, GLfloat * out, GLfloat u, GLfloat v,
GLuint dim, GLuint uorder, GLuint vorder)
{
GLfloat *cp = cn + uorder * vorder * dim;
GLuint i, uinc = vorder * dim;
if (vorder > uorder) {
if (uorder >= 2) {
GLfloat s, poweru, bincoeff;
GLuint j, k;
for (j = 0; j < vorder; j++) {
GLfloat *ucp = &cn[j * dim];
bincoeff = (GLfloat) (uorder - 1);
s = 1.0F - u;
for (k = 0; k < dim; k++)
cp[j * dim + k] = s * ucp[k] + bincoeff * u * ucp[uinc + k];
for (i = 2, ucp += 2 * uinc, poweru = u * u; i < uorder;
i++, poweru *= u, ucp += uinc) {
bincoeff *= (GLfloat) (uorder - i);
bincoeff *= inv_tab[i];
for (k = 0; k < dim; k++)
cp[j * dim + k] =
s * cp[j * dim + k] + bincoeff * poweru * ucp[k];
}
}
_math_horner_bezier_curve(cp, out, v, dim, vorder);
}
else
_math_horner_bezier_curve(cn, out, v, dim, vorder);
}
else {
if (vorder > 1) {
GLuint i;
for (i = 0; i < uorder; i++, cn += uinc) {
_math_horner_bezier_curve(cn, &cp[i * dim], v, dim, vorder);
}
_math_horner_bezier_curve(cp, out, u, dim, uorder);
}
else
_math_horner_bezier_curve(cn, out, u, dim, uorder);
}
}
void
_math_de_casteljau_surf(GLfloat * cn, GLfloat * out, GLfloat * du,
GLfloat * dv, GLfloat u, GLfloat v, GLuint dim,
GLuint uorder, GLuint vorder)
{
GLfloat *dcn = cn + uorder * vorder * dim;
GLfloat us = 1.0F - u, vs = 1.0F - v;
GLuint h, i, j, k;
GLuint minorder = uorder < vorder ? uorder : vorder;
GLuint uinc = vorder * dim;
GLuint dcuinc = vorder;
#define CN(I,J,K) cn[(I)*uinc+(J)*dim+(K)]
#define DCN(I, J) dcn[(I)*dcuinc+(J)]
if (minorder < 3) {
if (uorder == vorder) {
for (k = 0; k < dim; k++) {
du[k] = vs * (CN(1, 0, k) - CN(0, 0, k)) +
v * (CN(1, 1, k) - CN(0, 1, k));
dv[k] = us * (CN(0, 1, k) - CN(0, 0, k)) +
u * (CN(1, 1, k) - CN(1, 0, k));
out[k] = us * (vs * CN(0, 0, k) + v * CN(0, 1, k)) +
u * (vs * CN(1, 0, k) + v * CN(1, 1, k));
}
}
else if (minorder == uorder) {
for (k = 0; k < dim; k++) {
DCN(1, 0) = CN(1, 0, k) - CN(0, 0, k);
DCN(0, 0) = us * CN(0, 0, k) + u * CN(1, 0, k);
for (j = 0; j < vorder - 1; j++) {
DCN(1, j + 1) = CN(1, j + 1, k) - CN(0, j + 1, k);
DCN(1, j) = vs * DCN(1, j) + v * DCN(1, j + 1);
DCN(0, j + 1) = us * CN(0, j + 1, k) + u * CN(1, j + 1, k);
DCN(0, j) = vs * DCN(0, j) + v * DCN(0, j + 1);
}
for (h = minorder; h < vorder - 1; h++)
for (j = 0; j < vorder - h; j++) {
DCN(1, j) = vs * DCN(1, j) + v * DCN(1, j + 1);
DCN(0, j) = vs * DCN(0, j) + v * DCN(0, j + 1);
}
dv[k] = DCN(0, 1) - DCN(0, 0);
du[k] = vs * DCN(1, 0) + v * DCN(1, 1);
out[k] = vs * DCN(0, 0) + v * DCN(0, 1);
}
}
else {
for (k = 0; k < dim; k++) {
DCN(0, 1) = CN(0, 1, k) - CN(0, 0, k);
DCN(0, 0) = vs * CN(0, 0, k) + v * CN(0, 1, k);
for (i = 0; i < uorder - 1; i++) {
DCN(i + 1, 1) = CN(i + 1, 1, k) - CN(i + 1, 0, k);
DCN(i, 1) = us * DCN(i, 1) + u * DCN(i + 1, 1);
DCN(i + 1, 0) = vs * CN(i + 1, 0, k) + v * CN(i + 1, 1, k);
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
}
for (h = minorder; h < uorder - 1; h++)
for (i = 0; i < uorder - h; i++) {
DCN(i, 1) = us * DCN(i, 1) + u * DCN(i + 1, 1);
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
}
du[k] = DCN(1, 0) - DCN(0, 0);
dv[k] = us * DCN(0, 1) + u * DCN(1, 1);
out[k] = us * DCN(0, 0) + u * DCN(1, 0);
}
}
}
else if (uorder == vorder) {
for (k = 0; k < dim; k++) {
for (i = 0; i < uorder - 1; i++) {
DCN(i, 0) = us * CN(i, 0, k) + u * CN(i + 1, 0, k);
for (j = 0; j < vorder - 1; j++) {
DCN(i, j + 1) = us * CN(i, j + 1, k) + u * CN(i + 1, j + 1, k);
DCN(i, j) = vs * DCN(i, j) + v * DCN(i, j + 1);
}
}
for (h = 2; h < minorder - 1; h++)
for (i = 0; i < uorder - h; i++) {
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
for (j = 0; j < vorder - h; j++) {
DCN(i, j + 1) = us * DCN(i, j + 1) + u * DCN(i + 1, j + 1);
DCN(i, j) = vs * DCN(i, j) + v * DCN(i, j + 1);
}
}
du[k] = vs * (DCN(1, 0) - DCN(0, 0)) + v * (DCN(1, 1) - DCN(0, 1));
dv[k] = us * (DCN(0, 1) - DCN(0, 0)) + u * (DCN(1, 1) - DCN(1, 0));
out[k] = us * (vs * DCN(0, 0) + v * DCN(0, 1)) +
u * (vs * DCN(1, 0) + v * DCN(1, 1));
}
}
else if (minorder == uorder) {
for (k = 0; k < dim; k++) {
for (i = 0; i < uorder - 1; i++) {
DCN(i, 0) = us * CN(i, 0, k) + u * CN(i + 1, 0, k);
for (j = 0; j < vorder - 1; j++) {
DCN(i, j + 1) = us * CN(i, j + 1, k) + u * CN(i + 1, j + 1, k);
DCN(i, j) = vs * DCN(i, j) + v * DCN(i, j + 1);
}
}
for (h = 2; h < minorder - 1; h++)
for (i = 0; i < uorder - h; i++) {
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
for (j = 0; j < vorder - h; j++) {
DCN(i, j + 1) = us * DCN(i, j + 1) + u * DCN(i + 1, j + 1);
DCN(i, j) = vs * DCN(i, j) + v * DCN(i, j + 1);
}
}
DCN(2, 0) = DCN(1, 0) - DCN(0, 0);
DCN(0, 0) = us * DCN(0, 0) + u * DCN(1, 0);
for (j = 0; j < vorder - 1; j++) {
DCN(2, j + 1) = DCN(1, j + 1) - DCN(0, j + 1);
DCN(2, j) = vs * DCN(2, j) + v * DCN(2, j + 1);
DCN(0, j + 1) = us * DCN(0, j + 1) + u * DCN(1, j + 1);
DCN(0, j) = vs * DCN(0, j) + v * DCN(0, j + 1);
}
for (h = minorder; h < vorder - 1; h++)
for (j = 0; j < vorder - h; j++) {
DCN(2, j) = vs * DCN(2, j) + v * DCN(2, j + 1);
DCN(0, j) = vs * DCN(0, j) + v * DCN(0, j + 1);
}
dv[k] = DCN(0, 1) - DCN(0, 0);
du[k] = vs * DCN(2, 0) + v * DCN(2, 1);
out[k] = vs * DCN(0, 0) + v * DCN(0, 1);
}
}
else {
for (k = 0; k < dim; k++) {
for (i = 0; i < uorder - 1; i++) {
DCN(i, 0) = us * CN(i, 0, k) + u * CN(i + 1, 0, k);
for (j = 0; j < vorder - 1; j++) {
DCN(i, j + 1) = us * CN(i, j + 1, k) + u * CN(i + 1, j + 1, k);
DCN(i, j) = vs * DCN(i, j) + v * DCN(i, j + 1);
}
}
for (h = 2; h < minorder - 1; h++)
for (i = 0; i < uorder - h; i++) {
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
for (j = 0; j < vorder - h; j++) {
DCN(i, j + 1) = us * DCN(i, j + 1) + u * DCN(i + 1, j + 1);
DCN(i, j) = vs * DCN(i, j) + v * DCN(i, j + 1);
}
}
DCN(0, 2) = DCN(0, 1) - DCN(0, 0);
DCN(0, 0) = vs * DCN(0, 0) + v * DCN(0, 1);
for (i = 0; i < uorder - 1; i++) {
DCN(i + 1, 2) = DCN(i + 1, 1) - DCN(i + 1, 0);
DCN(i, 2) = us * DCN(i, 2) + u * DCN(i + 1, 2);
DCN(i + 1, 0) = vs * DCN(i + 1, 0) + v * DCN(i + 1, 1);
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
}
for (h = minorder; h < uorder - 1; h++)
for (i = 0; i < uorder - h; i++) {
DCN(i, 2) = us * DCN(i, 2) + u * DCN(i + 1, 2);
DCN(i, 0) = us * DCN(i, 0) + u * DCN(i + 1, 0);
}
du[k] = DCN(1, 0) - DCN(0, 0);
dv[k] = us * DCN(0, 2) + u * DCN(1, 2);
out[k] = us * DCN(0, 0) + u * DCN(1, 0);
}
}
#undef DCN
#undef CN
}
void
_math_init_eval(void)
{
GLuint i;
for (i = 1; i < MAX_EVAL_ORDER; i++)
inv_tab[i] = 1.0F / i;
}