sosc_test/include/cglm/cam.h
2020-12-10 14:42:39 -06:00

582 lines
15 KiB
C

/*
* Copyright (c), Recep Aslantas.
*
* MIT License (MIT), http://opensource.org/licenses/MIT
* Full license can be found in the LICENSE file
*/
/*
Functions:
CGLM_INLINE void glm_frustum(float left, float right,
float bottom, float top,
float nearVal, float farVal,
mat4 dest)
CGLM_INLINE void glm_ortho(float left, float right,
float bottom, float top,
float nearVal, float farVal,
mat4 dest)
CGLM_INLINE void glm_ortho_aabb(vec3 box[2], mat4 dest)
CGLM_INLINE void glm_ortho_aabb_p(vec3 box[2], float padding, mat4 dest)
CGLM_INLINE void glm_ortho_aabb_pz(vec3 box[2], float padding, mat4 dest)
CGLM_INLINE void glm_ortho_default(float aspect, mat4 dest)
CGLM_INLINE void glm_ortho_default_s(float aspect, float size, mat4 dest)
CGLM_INLINE void glm_perspective(float fovy,
float aspect,
float nearVal,
float farVal,
mat4 dest)
CGLM_INLINE void glm_perspective_default(float aspect, mat4 dest)
CGLM_INLINE void glm_perspective_resize(float aspect, mat4 proj)
CGLM_INLINE void glm_lookat(vec3 eye, vec3 center, vec3 up, mat4 dest)
CGLM_INLINE void glm_look(vec3 eye, vec3 dir, vec3 up, mat4 dest)
CGLM_INLINE void glm_look_anyup(vec3 eye, vec3 dir, mat4 dest)
CGLM_INLINE void glm_persp_decomp(mat4 proj,
float *nearVal, float *farVal,
float *top, float *bottom,
float *left, float *right)
CGLM_INLINE void glm_persp_decompv(mat4 proj, float dest[6])
CGLM_INLINE void glm_persp_decomp_x(mat4 proj, float *left, float *right)
CGLM_INLINE void glm_persp_decomp_y(mat4 proj, float *top, float *bottom)
CGLM_INLINE void glm_persp_decomp_z(mat4 proj, float *nearv, float *farv)
CGLM_INLINE void glm_persp_decomp_far(mat4 proj, float *farVal)
CGLM_INLINE void glm_persp_decomp_near(mat4 proj, float *nearVal)
CGLM_INLINE float glm_persp_fovy(mat4 proj)
CGLM_INLINE float glm_persp_aspect(mat4 proj)
CGLM_INLINE void glm_persp_sizes(mat4 proj, float fovy, vec4 dest)
*/
#ifndef cglm_vcam_h
#define cglm_vcam_h
#include "common.h"
#include "plane.h"
/*!
* @brief set up perspective peprojection matrix
*
* @param[in] left viewport.left
* @param[in] right viewport.right
* @param[in] bottom viewport.bottom
* @param[in] top viewport.top
* @param[in] nearVal near clipping plane
* @param[in] farVal far clipping plane
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_frustum(float left, float right,
float bottom, float top,
float nearVal, float farVal,
mat4 dest) {
float rl, tb, fn, nv;
glm_mat4_zero(dest);
rl = 1.0f / (right - left);
tb = 1.0f / (top - bottom);
fn =-1.0f / (farVal - nearVal);
nv = 2.0f * nearVal;
dest[0][0] = nv * rl;
dest[1][1] = nv * tb;
dest[2][0] = (right + left) * rl;
dest[2][1] = (top + bottom) * tb;
dest[2][2] = (farVal + nearVal) * fn;
dest[2][3] =-1.0f;
dest[3][2] = farVal * nv * fn;
}
/*!
* @brief set up orthographic projection matrix
*
* @param[in] left viewport.left
* @param[in] right viewport.right
* @param[in] bottom viewport.bottom
* @param[in] top viewport.top
* @param[in] nearVal near clipping plane
* @param[in] farVal far clipping plane
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_ortho(float left, float right,
float bottom, float top,
float nearVal, float farVal,
mat4 dest) {
float rl, tb, fn;
glm_mat4_zero(dest);
rl = 1.0f / (right - left);
tb = 1.0f / (top - bottom);
fn =-1.0f / (farVal - nearVal);
dest[0][0] = 2.0f * rl;
dest[1][1] = 2.0f * tb;
dest[2][2] = 2.0f * fn;
dest[3][0] =-(right + left) * rl;
dest[3][1] =-(top + bottom) * tb;
dest[3][2] = (farVal + nearVal) * fn;
dest[3][3] = 1.0f;
}
/*!
* @brief set up orthographic projection matrix using bounding box
*
* bounding box (AABB) must be in view space
*
* @param[in] box AABB
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_ortho_aabb(vec3 box[2], mat4 dest) {
glm_ortho(box[0][0], box[1][0],
box[0][1], box[1][1],
-box[1][2], -box[0][2],
dest);
}
/*!
* @brief set up orthographic projection matrix using bounding box
*
* bounding box (AABB) must be in view space
*
* @param[in] box AABB
* @param[in] padding padding
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_ortho_aabb_p(vec3 box[2], float padding, mat4 dest) {
glm_ortho(box[0][0] - padding, box[1][0] + padding,
box[0][1] - padding, box[1][1] + padding,
-(box[1][2] + padding), -(box[0][2] - padding),
dest);
}
/*!
* @brief set up orthographic projection matrix using bounding box
*
* bounding box (AABB) must be in view space
*
* @param[in] box AABB
* @param[in] padding padding for near and far
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_ortho_aabb_pz(vec3 box[2], float padding, mat4 dest) {
glm_ortho(box[0][0], box[1][0],
box[0][1], box[1][1],
-(box[1][2] + padding), -(box[0][2] - padding),
dest);
}
/*!
* @brief set up unit orthographic projection matrix
*
* @param[in] aspect aspect ration ( width / height )
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_ortho_default(float aspect, mat4 dest) {
if (aspect >= 1.0f) {
glm_ortho(-aspect, aspect, -1.0f, 1.0f, -100.0f, 100.0f, dest);
return;
}
aspect = 1.0f / aspect;
glm_ortho(-1.0f, 1.0f, -aspect, aspect, -100.0f, 100.0f, dest);
}
/*!
* @brief set up orthographic projection matrix with given CUBE size
*
* @param[in] aspect aspect ratio ( width / height )
* @param[in] size cube size
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_ortho_default_s(float aspect, float size, mat4 dest) {
if (aspect >= 1.0f) {
glm_ortho(-size * aspect,
size * aspect,
-size,
size,
-size - 100.0f,
size + 100.0f,
dest);
return;
}
glm_ortho(-size,
size,
-size / aspect,
size / aspect,
-size - 100.0f,
size + 100.0f,
dest);
}
/*!
* @brief set up perspective projection matrix
*
* @param[in] fovy field of view angle
* @param[in] aspect aspect ratio ( width / height )
* @param[in] nearVal near clipping plane
* @param[in] farVal far clipping planes
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_perspective(float fovy,
float aspect,
float nearVal,
float farVal,
mat4 dest) {
float f, fn;
glm_mat4_zero(dest);
f = 1.0f / tanf(fovy * 0.5f);
fn = 1.0f / (nearVal - farVal);
dest[0][0] = f / aspect;
dest[1][1] = f;
dest[2][2] = (nearVal + farVal) * fn;
dest[2][3] =-1.0f;
dest[3][2] = 2.0f * nearVal * farVal * fn;
}
/*!
* @brief extend perspective projection matrix's far distance
*
* this function does not guarantee far >= near, be aware of that!
*
* @param[in, out] proj projection matrix to extend
* @param[in] deltaFar distance from existing far (negative to shink)
*/
CGLM_INLINE
void
glm_persp_move_far(mat4 proj, float deltaFar) {
float fn, farVal, nearVal, p22, p32;
p22 = proj[2][2];
p32 = proj[3][2];
nearVal = p32 / (p22 - 1.0f);
farVal = p32 / (p22 + 1.0f) + deltaFar;
fn = 1.0f / (nearVal - farVal);
proj[2][2] = (nearVal + farVal) * fn;
proj[3][2] = 2.0f * nearVal * farVal * fn;
}
/*!
* @brief set up perspective projection matrix with default near/far
* and angle values
*
* @param[in] aspect aspect ratio ( width / height )
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_perspective_default(float aspect, mat4 dest) {
glm_perspective(GLM_PI_4f, aspect, 0.01f, 100.0f, dest);
}
/*!
* @brief resize perspective matrix by aspect ratio ( width / height )
* this makes very easy to resize proj matrix when window /viewport
* reized
*
* @param[in] aspect aspect ratio ( width / height )
* @param[in, out] proj perspective projection matrix
*/
CGLM_INLINE
void
glm_perspective_resize(float aspect, mat4 proj) {
if (proj[0][0] == 0.0f)
return;
proj[0][0] = proj[1][1] / aspect;
}
/*!
* @brief set up view matrix
*
* NOTE: The UP vector must not be parallel to the line of sight from
* the eye point to the reference point
*
* @param[in] eye eye vector
* @param[in] center center vector
* @param[in] up up vector
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_lookat(vec3 eye, vec3 center, vec3 up, mat4 dest) {
CGLM_ALIGN(8) vec3 f, u, s;
glm_vec3_sub(center, eye, f);
glm_vec3_normalize(f);
glm_vec3_crossn(f, up, s);
glm_vec3_cross(s, f, u);
dest[0][0] = s[0];
dest[0][1] = u[0];
dest[0][2] =-f[0];
dest[1][0] = s[1];
dest[1][1] = u[1];
dest[1][2] =-f[1];
dest[2][0] = s[2];
dest[2][1] = u[2];
dest[2][2] =-f[2];
dest[3][0] =-glm_vec3_dot(s, eye);
dest[3][1] =-glm_vec3_dot(u, eye);
dest[3][2] = glm_vec3_dot(f, eye);
dest[0][3] = dest[1][3] = dest[2][3] = 0.0f;
dest[3][3] = 1.0f;
}
/*!
* @brief set up view matrix
*
* convenient wrapper for lookat: if you only have direction not target self
* then this might be useful. Because you need to get target from direction.
*
* NOTE: The UP vector must not be parallel to the line of sight from
* the eye point to the reference point
*
* @param[in] eye eye vector
* @param[in] dir direction vector
* @param[in] up up vector
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_look(vec3 eye, vec3 dir, vec3 up, mat4 dest) {
CGLM_ALIGN(8) vec3 target;
glm_vec3_add(eye, dir, target);
glm_lookat(eye, target, up, dest);
}
/*!
* @brief set up view matrix
*
* convenient wrapper for look: if you only have direction and if you don't
* care what UP vector is then this might be useful to create view matrix
*
* @param[in] eye eye vector
* @param[in] dir direction vector
* @param[out] dest result matrix
*/
CGLM_INLINE
void
glm_look_anyup(vec3 eye, vec3 dir, mat4 dest) {
CGLM_ALIGN(8) vec3 up;
glm_vec3_ortho(dir, up);
glm_look(eye, dir, up, dest);
}
/*!
* @brief decomposes frustum values of perspective projection.
*
* @param[in] proj perspective projection matrix
* @param[out] nearVal near
* @param[out] farVal far
* @param[out] top top
* @param[out] bottom bottom
* @param[out] left left
* @param[out] right right
*/
CGLM_INLINE
void
glm_persp_decomp(mat4 proj,
float * __restrict nearVal, float * __restrict farVal,
float * __restrict top, float * __restrict bottom,
float * __restrict left, float * __restrict right) {
float m00, m11, m20, m21, m22, m32, n, f;
float n_m11, n_m00;
m00 = proj[0][0];
m11 = proj[1][1];
m20 = proj[2][0];
m21 = proj[2][1];
m22 = proj[2][2];
m32 = proj[3][2];
n = m32 / (m22 - 1.0f);
f = m32 / (m22 + 1.0f);
n_m11 = n / m11;
n_m00 = n / m00;
*nearVal = n;
*farVal = f;
*bottom = n_m11 * (m21 - 1.0f);
*top = n_m11 * (m21 + 1.0f);
*left = n_m00 * (m20 - 1.0f);
*right = n_m00 * (m20 + 1.0f);
}
/*!
* @brief decomposes frustum values of perspective projection.
* this makes easy to get all values at once
*
* @param[in] proj perspective projection matrix
* @param[out] dest array
*/
CGLM_INLINE
void
glm_persp_decompv(mat4 proj, float dest[6]) {
glm_persp_decomp(proj, &dest[0], &dest[1], &dest[2],
&dest[3], &dest[4], &dest[5]);
}
/*!
* @brief decomposes left and right values of perspective projection.
* x stands for x axis (left / right axis)
*
* @param[in] proj perspective projection matrix
* @param[out] left left
* @param[out] right right
*/
CGLM_INLINE
void
glm_persp_decomp_x(mat4 proj,
float * __restrict left,
float * __restrict right) {
float nearVal, m20, m00;
m00 = proj[0][0];
m20 = proj[2][0];
nearVal = proj[3][2] / (proj[3][3] - 1.0f);
*left = nearVal * (m20 - 1.0f) / m00;
*right = nearVal * (m20 + 1.0f) / m00;
}
/*!
* @brief decomposes top and bottom values of perspective projection.
* y stands for y axis (top / botom axis)
*
* @param[in] proj perspective projection matrix
* @param[out] top top
* @param[out] bottom bottom
*/
CGLM_INLINE
void
glm_persp_decomp_y(mat4 proj,
float * __restrict top,
float * __restrict bottom) {
float nearVal, m21, m11;
m21 = proj[2][1];
m11 = proj[1][1];
nearVal = proj[3][2] / (proj[3][3] - 1.0f);
*bottom = nearVal * (m21 - 1) / m11;
*top = nearVal * (m21 + 1) / m11;
}
/*!
* @brief decomposes near and far values of perspective projection.
* z stands for z axis (near / far axis)
*
* @param[in] proj perspective projection matrix
* @param[out] nearVal near
* @param[out] farVal far
*/
CGLM_INLINE
void
glm_persp_decomp_z(mat4 proj,
float * __restrict nearVal,
float * __restrict farVal) {
float m32, m22;
m32 = proj[3][2];
m22 = proj[2][2];
*nearVal = m32 / (m22 - 1.0f);
*farVal = m32 / (m22 + 1.0f);
}
/*!
* @brief decomposes far value of perspective projection.
*
* @param[in] proj perspective projection matrix
* @param[out] farVal far
*/
CGLM_INLINE
void
glm_persp_decomp_far(mat4 proj, float * __restrict farVal) {
*farVal = proj[3][2] / (proj[2][2] + 1.0f);
}
/*!
* @brief decomposes near value of perspective projection.
*
* @param[in] proj perspective projection matrix
* @param[out] nearVal near
*/
CGLM_INLINE
void
glm_persp_decomp_near(mat4 proj, float * __restrict nearVal) {
*nearVal = proj[3][2] / (proj[2][2] - 1.0f);
}
/*!
* @brief returns field of view angle along the Y-axis (in radians)
*
* if you need to degrees, use glm_deg to convert it or use this:
* fovy_deg = glm_deg(glm_persp_fovy(projMatrix))
*
* @param[in] proj perspective projection matrix
*/
CGLM_INLINE
float
glm_persp_fovy(mat4 proj) {
return 2.0f * atanf(1.0f / proj[1][1]);
}
/*!
* @brief returns aspect ratio of perspective projection
*
* @param[in] proj perspective projection matrix
*/
CGLM_INLINE
float
glm_persp_aspect(mat4 proj) {
return proj[1][1] / proj[0][0];
}
/*!
* @brief returns sizes of near and far planes of perspective projection
*
* @param[in] proj perspective projection matrix
* @param[in] fovy fovy (see brief)
* @param[out] dest sizes order: [Wnear, Hnear, Wfar, Hfar]
*/
CGLM_INLINE
void
glm_persp_sizes(mat4 proj, float fovy, vec4 dest) {
float t, a, nearVal, farVal;
t = 2.0f * tanf(fovy * 0.5f);
a = glm_persp_aspect(proj);
glm_persp_decomp_z(proj, &nearVal, &farVal);
dest[1] = t * nearVal;
dest[3] = t * farVal;
dest[0] = a * dest[1];
dest[2] = a * dest[3];
}
#endif /* cglm_vcam_h */