-/* gph-cmath - C graphics math library
- * Copyright (C) 2018 John Tsiombikas <nuclear@member.fsf.org>
- *
- * This program is free software. Feel free to use, modify, and/or redistribute
- * it under the terms of the MIT/X11 license. See LICENSE for details.
- * If you intend to redistribute parts of the code without the LICENSE file
- * replace this paragraph with the full contents of the LICENSE file.
- */
-static inline void cgm_mcopy(float *dest, const float *src)
-{
- memcpy(dest, src, 16 * sizeof(float));
-}
-
-static inline void cgm_mzero(float *m)
-{
- static float z[16];
- cgm_mcopy(m, z);
-}
-
-static inline void cgm_midentity(float *m)
-{
- static float id[16] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
- cgm_mcopy(m, id);
-}
-
-static inline void cgm_mmul(float *a, const float *b)
-{
- int i, j;
- float res[16];
- float *resptr = res;
- float *arow = a;
-
- for(i=0; i<4; i++) {
- for(j=0; j<4; j++) {
- *resptr++ = arow[0] * b[j] + arow[1] * b[4 + j] +
- arow[2] * b[8 + j] + arow[3] * b[12 + j];
- }
- arow += 4;
- }
- cgm_mcopy(a, res);
-}
-
-static inline void cgm_msubmatrix(float *m, int row, int col)
-{
- float orig[16];
- int i, j, subi, subj;
-
- cgm_mcopy(orig, m);
-
- subi = 0;
- for(i=0; i<4; i++) {
- if(i == row) continue;
-
- subj = 0;
- for(j=0; j<4; j++) {
- if(j == col) continue;
-
- m[subi * 4 + subj++] = orig[i * 4 + j];
- }
- subi++;
- }
-
- cgm_mupper3(m);
-}
-
-static inline void cgm_mupper3(float *m)
-{
- m[3] = m[7] = m[11] = m[12] = m[13] = m[14] = 0.0f;
- m[15] = 1.0f;
-}
-
-static inline float cgm_msubdet(const float *m, int row, int col)
-{
- float tmp[16];
- float subdet00, subdet01, subdet02;
-
- cgm_mcopy(tmp, m);
- cgm_msubmatrix(tmp, row, col);
-
- subdet00 = tmp[5] * tmp[10] - tmp[6] * tmp[9];
- subdet01 = tmp[4] * tmp[10] - tmp[6] * tmp[8];
- subdet02 = tmp[4] * tmp[9] - tmp[5] * tmp[8];
-
- return tmp[0] * subdet00 - tmp[1] * subdet01 + tmp[2] * subdet02;
-}
-
-static inline float cgm_mcofactor(const float *m, int row, int col)
-{
- float min = cgm_msubdet(m, row, col);
- return (row + col) & 1 ? -min : min;
-}
-
-static inline float cgm_mdet(const float *m)
-{
- return m[0] * cgm_msubdet(m, 0, 0) - m[1] * cgm_msubdet(m, 0, 1) +
- m[2] * cgm_msubdet(m, 0, 2) - m[3] * cgm_msubdet(m, 0, 3);
-}
-
-static inline void cgm_mtranspose(float *m)
-{
- int i, j;
- for(i=0; i<4; i++) {
- for(j=0; j<i; j++) {
- int a = i * 4 + j;
- int b = j * 4 + i;
- float tmp = m[a];
- m[a] = m[b];
- m[b] = tmp;
- }
- }
-}
-
-static inline void cgm_mcofmatrix(float *m)
-{
- float tmp[16];
- int i, j;
-
- cgm_mcopy(tmp, m);
-
- for(i=0; i<4; i++) {
- for(j=0; j<4; j++) {
- m[i * 4 + j] = cgm_mcofactor(tmp, i, j);
- }
- }
-}
-
-static inline int cgm_minverse(float *m)
-{
- int i, j;
- float tmp[16];
- float inv_det;
- float det = cgm_mdet(m);
- if(det == 0.0f) return -1;
- inv_det = 1.0f / det;
-
- cgm_mcopy(tmp, m);
-
- for(i=0; i<4; i++) {
- for(j=0; j<4; j++) {
- m[i * 4 + j] = cgm_mcofactor(tmp, j, i) * inv_det; /* transposed */
- }
- }
- return 0;
-}
-
-static inline void cgm_mtranslation(float *m, float x, float y, float z)
-{
- cgm_midentity(m);
- m[12] = x;
- m[13] = y;
- m[14] = z;
-}
-
-static inline void cgm_mscaling(float *m, float sx, float sy, float sz)
-{
- cgm_mzero(m);
- m[0] = sx;
- m[5] = sy;
- m[10] = sz;
- m[15] = 1.0f;
-}
-
-static inline void cgm_mrotation_x(float *m, float angle)
-{
- float sa = sin(angle);
- float ca = cos(angle);
-
- cgm_midentity(m);
- m[5] = ca;
- m[6] = sa;
- m[9] = -sa;
- m[10] = ca;
-}
-
-static inline void cgm_mrotation_y(float *m, float angle)
-{
- float sa = sin(angle);
- float ca = cos(angle);
-
- cgm_midentity(m);
- m[0] = ca;
- m[2] = -sa;
- m[8] = sa;
- m[10] = ca;
-}
-
-static inline void cgm_mrotation_z(float *m, float angle)
-{
- float sa = sin(angle);
- float ca = cos(angle);
-
- cgm_midentity(m);
- m[0] = ca;
- m[1] = sa;
- m[4] = -sa;
- m[5] = ca;
-}
-
-static inline void cgm_mrotation_axis(float *m, int idx, float angle)
-{
- switch(idx) {
- case 0:
- cgm_mrotation_x(m, angle);
- break;
- case 1:
- cgm_mrotation_y(m, angle);
- break;
- case 2:
- cgm_mrotation_z(m, angle);
- break;
- }
-}
-
-static inline void cgm_mrotation(float *m, float angle, float x, float y, float z)
-{
- float sa = sin(angle);
- float ca = cos(angle);
- float invca = 1.0f - ca;
- float xsq = x * x;
- float ysq = y * y;
- float zsq = z * z;
-
- cgm_mzero(m);
- m[15] = 1.0f;
-
- m[0] = xsq + (1.0f - xsq) * ca;
- m[4] = x * y * invca - z * sa;
- m[8] = x * z * invca + y * sa;
-
- m[1] = x * y * invca + z * sa;
- m[5] = ysq + (1.0f - ysq) * ca;
- m[9] = y * z * invca - x * sa;
-
- m[2] = x * z * invca - y * sa;
- m[6] = y * z * invca + x * sa;
- m[10] = zsq + (1.0f - zsq) * ca;
-}
-
-static inline void cgm_mrotation_euler(float *m, float a, float b, float c, int mode)
-{
- /* this array must match the EulerMode enum */
- static const int axis[][3] = {
- {0, 1, 2}, {0, 2, 1},
- {1, 0, 2}, {1, 2, 0},
- {2, 0, 1}, {2, 1, 0},
- {2, 0, 2}, {2, 1, 2},
- {1, 0, 1}, {1, 2, 1},
- {0, 1, 0}, {0, 2, 0}
- };
-
- float ma[16], mb[16];
- cgm_mrotation_axis(ma, axis[mode][0], a);
- cgm_mrotation_axis(mb, axis[mode][1], b);
- cgm_mrotation_axis(m, axis[mode][2], c);
- cgm_mmul(m, mb);
- cgm_mmul(m, ma);
-}
-
-static inline void cgm_mtranslate(float *m, float x, float y, float z)
-{
- float tm[16];
- cgm_mtranslation(tm, x, y, z);
- cgm_mmul(m, tm);
-}
-
-static inline void cgm_mscale(float *m, float sx, float sy, float sz)
-{
- float sm[16];
- cgm_mscaling(sm, sx, sy, sz);
- cgm_mmul(m, sm);
-}
-
-static inline void cgm_mrotate_x(float *m, float angle)
-{
- float rm[16];
- cgm_mrotation_x(rm, angle);
- cgm_mmul(m, rm);
-}
-
-static inline void cgm_mrotate_y(float *m, float angle)
-{
- float rm[16];
- cgm_mrotation_y(rm, angle);
- cgm_mmul(m, rm);
-}
-
-static inline void cgm_mrotate_z(float *m, float angle)
-{
- float rm[16];
- cgm_mrotation_z(rm, angle);
- cgm_mmul(m, rm);
-}
-
-static inline void cgm_mrotate_axis(float *m, int idx, float angle)
-{
- float rm[16];
- cgm_mrotation_axis(rm, idx, angle);
- cgm_mmul(m, rm);
-}
-
-static inline void cgm_mrotate(float *m, float angle, float x, float y, float z)
-{
- float rm[16];
- cgm_mrotation(rm, angle, x, y, z);
- cgm_mmul(m, rm);
-}
-
-static inline void cgm_mrotate_euler(float *m, float a, float b, float c, int mode)
-{
- float rm[16];
- cgm_mrotation_euler(rm, a, b, c, mode);
- cgm_mmul(m, rm);
-}
-
-
-static inline void cgm_mpretranslate(float *m, float x, float y, float z)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mtranslation(m, x, y, z);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprescale(float *m, float sx, float sy, float sz)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mscaling(m, sx, sy, sz);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprerotate_x(float *m, float angle)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mrotation_x(m, angle);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprerotate_y(float *m, float angle)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mrotation_y(m, angle);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprerotate_z(float *m, float angle)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mrotation_z(m, angle);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprerotate_axis(float *m, int idx, float angle)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mrotation_axis(m, idx, angle);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprerotate(float *m, float angle, float x, float y, float z)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mrotation(m, angle, x, y, z);
- cgm_mmul(m, tmp);
-}
-
-static inline void cgm_mprerotate_euler(float *m, float a, float b, float c, int mode)
-{
- float tmp[16];
- cgm_mcopy(tmp, m);
- cgm_mrotation_euler(m, a, b, c, mode);
- cgm_mmul(m, tmp);
-}
-
-
-static inline void cgm_mget_translation(const float *m, cgm_vec3 *res)
-{
- res->x = m[12];
- res->y = m[13];
- res->z = m[14];
-}
-
-/* Algorithm in Ken Shoemake's article in 1987 SIGGRAPH course notes
- * article "Quaternion Calculus and Fast Animation".
- * adapted from: http://www.geometrictools.com/LibMathematics/Algebra/Wm5Quaternion.inl
- */
-static inline void cgm_mget_rotation(const float *m, cgm_quat *res)
-{
- static const int next[3] = {1, 2, 0};
- float quat[4];
- int i, j, k;
-
- float trace = m[0] + m[5] + m[10];
- float root;
-
- if(trace > 0.0f) {
- // |w| > 1/2
- root = sqrt(trace + 1.0f); // 2w
- res->w = 0.5f * root;
- root = 0.5f / root; // 1 / 4w
- res->x = (m[6] - m[9]) * root;
- res->y = (m[8] - m[2]) * root;
- res->z = (m[1] - m[4]) * root;
- } else {
- // |w| <= 1/2
- i = 0;
- if(m[5] > m[0]) {
- i = 1;
- }
- if(m[10] > m[i * 4 + i]) {
- i = 2;
- }
- j = next[i];
- k = next[j];
-
- root = sqrt(m[i * 4 + i] - m[j * 4 + j] - m[k * 4 + k] + 1.0f);
- quat[i + 1] = 0.5f * root;
- root = 0.5f / root;
- quat[0] = (m[j + 4 + k] - m[k * 4 + j]) * root;
- quat[j + 1] = (m[i * 4 + j] - m[j * 4 + i]) * root;
- quat[k + 1] = (m[i * 4 + k] - m[k * 4 + i]) * root;
- res->w = quat[0];
- res->x = quat[1];
- res->y = quat[2];
- res->z = quat[3];
- }
-}
-
-static inline void cgm_mget_scaling(const float *m, cgm_vec3 *res)
-{
- res->x = sqrt(m[0] * m[0] + m[4] * m[4] + m[8] * m[8]);
- res->y = sqrt(m[1] * m[1] + m[5] * m[5] + m[9] * m[9]);
- res->z = sqrt(m[2] * m[2] + m[6] * m[6] + m[10] * m[10]);
-}
-
-static inline void cgm_mget_frustum_plane(const float *m, int p, cgm_vec4 *res)
-{
- int row = p >> 1;
- const float *rowptr = m + row * 4;
-
- if((p & 1) == 0) {
- res->x = m[12] + rowptr[0];
- res->y = m[13] + rowptr[1];
- res->z = m[14] + rowptr[2];
- res->w = m[15] + rowptr[3];
- } else {
- res->x = m[12] - rowptr[0];
- res->y = m[13] - rowptr[1];
- res->z = m[14] - rowptr[2];
- res->w = m[15] - rowptr[3];
- }
-}
-
-static inline void cgm_mlookat(float *m, const cgm_vec3 *pos, const cgm_vec3 *targ,
- const cgm_vec3 *up)
-{
- float trans[16];
- cgm_vec3 dir = *targ, right, vup;
-
- cgm_vsub(&dir, pos);
- cgm_vnormalize(&dir);
- cgm_vcross(&right, &dir, up);
- cgm_vnormalize(&right);
- cgm_vcross(&vup, &right, &dir);
- cgm_vnormalize(&vup);
-
- cgm_midentity(m);
- m[0] = right.x;
- m[1] = right.y;
- m[2] = right.z;
- m[4] = vup.x;
- m[5] = vup.y;
- m[6] = vup.z;
- m[8] = -dir.x;
- m[9] = -dir.y;
- m[10] = -dir.z;
-
- cgm_mtranslation(trans, pos->x, pos->y, pos->z);
- cgm_mmul(m, trans);
-}
-
-static inline void cgm_minv_lookat(float *m, const cgm_vec3 *pos, const cgm_vec3 *targ,
- const cgm_vec3 *up)
-{
- float rot[16];
- cgm_vec3 dir = *targ, right, vup;
-
- cgm_vsub(&dir, pos);
- cgm_vnormalize(&dir);
- cgm_vcross(&right, &dir, up);
- cgm_vnormalize(&right);
- cgm_vcross(&vup, &right, &dir);
- cgm_vnormalize(&vup);
-
- cgm_midentity(rot);
- rot[0] = right.x;
- rot[4] = right.y;
- rot[8] = right.z;
- rot[1] = vup.x;
- rot[5] = vup.y;
- rot[9] = vup.z;
- rot[2] = -dir.x;
- rot[6] = -dir.y;
- rot[10] = -dir.z;
-
- cgm_mtranslation(m, -pos->x, -pos->y, -pos->z);
- cgm_mmul(m, rot);
-}
-
-static inline void cgm_mortho(float *m, float left, float right, float bot, float top,
- float znear, float zfar)
-{
- float dx = right - left;
- float dy = top - bot;
- float dz = zfar - znear;
-
- cgm_midentity(m);
- m[0] = 2.0f / dx;
- m[5] = 2.0f / dy;
- m[10] = -2.0f / dz;
- m[12] = -(right + left) / dx;
- m[13] = -(top + bot) / dy;
- m[14] = -(zfar + znear) / dz;
-}
-
-static inline void cgm_mfrustum(float *m, float left, float right, float bot, float top,
- float znear, float zfar)
-{
- float dx = right - left;
- float dy = top - bot;
- float dz = zfar - znear;
-
- cgm_mzero(m);
- m[0] = 2.0f * znear / dx;
- m[5] = 2.0f * znear / dy;
- m[8] = (right + left) / dx;
- m[9] = (top + bot) / dy;
- m[10] = -(zfar + znear) / dz;
- m[14] = -2.0f * zfar * znear / dz;
- m[11] = -1.0f;
-}
-
-static inline void cgm_mperspective(float *m, float vfov, float aspect, float znear, float zfar)
-{
- float s = 1.0f / (float)tan(vfov / 2.0f);
- float range = znear - zfar;
-
- cgm_mzero(m);
- m[0] = s / aspect;
- m[5] = s;
- m[10] = (znear + zfar) / range;
- m[14] = 2.0f * znear * zfar / range;
- m[11] = -1.0f;
-}
-
-static inline void cgm_mmirror(float *m, float a, float b, float c, float d)
-{
- m[0] = 1.0f - 2.0f * a * a;
- m[5] = 1.0f - 2.0f * b * b;
- m[10] = 1.0f - 2.0f * c * c;
- m[15] = 1.0f;
-
- m[1] = m[4] = -2.0f * a * b;
- m[2] = m[8] = -2.0f * a * c;
- m[6] = m[9] = -2.0f * b * c;
-
- m[12] = -2.0f * a * d;
- m[13] = -2.0f * b * d;
- m[14] = -2.0f * c * d;
-
- m[3] = m[7] = m[11] = 0.0f;
-}