+/*
+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));
subi = 0;
for(i=0; i<4; i++) {
- if(i == col) continue;
+ if(i == row) continue;
subj = 0;
for(j=0; j<4; j++) {
- if(j == row) continue;
+ if(j == col) continue;
m[subi * 4 + subj++] = orig[i * 4 + j];
}
m[15] = 1.0f;
}
-static inline float cgm_msubdet(float *m, int row, int col)
+static inline float cgm_msubdet(const float *m, int row, int col)
{
- cgm_msubmatrix(m, row, col);
- return cgm_mdet(m);
+ 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(float *m, int row, int col)
+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(float *m)
+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);
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)
static inline void cgm_mlookat(float *m, const cgm_vec3 *pos, const cgm_vec3 *targ,
const cgm_vec3 *up)
{
- float rot[16], trans[16];
- cgm_vec3 dir = targ, right, vup;
+ float trans[16];
+ cgm_vec3 dir = *targ, right, vup;
cgm_vsub(&dir, pos);
cgm_vnormalize(&dir);
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;
- rot[0] = right.x;
- /* TODO cont. */
+ 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);
+ 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 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);
-static inline void cgm_mperspective(float *m, float vfov, float aspect, float znear, float zfar);
+ float znear, float zfar)
+{
+ float dx = right - left;
+ float dy = top - bot;
+ float dz = zfar - znear;
-static inline void cgm_mmirror(float *m, float a, float b, float c, float d);
+ 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;
+}
projects / gph-cmath / blobdiff