orbit-plus/include/cglm/struct/project.h
2023-02-11 23:18:45 -05:00

121 lines
3.2 KiB
C

/*
* Copyright (c), Recep Aslantas.
*
* MIT License (MIT), http://opensource.org/licenses/MIT
* Full license can be found in the LICENSE file
*/
#ifndef cglms_projects_h
#define cglms_projects_h
#include "../common.h"
#include "../types-struct.h"
#include "../project.h"
#include "vec3.h"
#include "vec4.h"
#include "mat4.h"
/*!
* @brief maps the specified viewport coordinates into specified space [1]
* the matrix should contain projection matrix.
*
* if you don't have ( and don't want to have ) an inverse matrix then use
* glm_unproject version. You may use existing inverse of matrix in somewhere
* else, this is why glm_unprojecti exists to save save inversion cost
*
* [1] space:
* 1- if m = invProj: View Space
* 2- if m = invViewProj: World Space
* 3- if m = invMVP: Object Space
*
* You probably want to map the coordinates into object space
* so use invMVP as m
*
* Computing viewProj:
* glm_mat4_mul(proj, view, viewProj);
* glm_mat4_mul(viewProj, model, MVP);
* glm_mat4_inv(viewProj, invMVP);
*
* @param[in] pos point/position in viewport coordinates
* @param[in] invMat matrix (see brief)
* @param[in] vp viewport as [x, y, width, height]
* @returns unprojected coordinates
*/
CGLM_INLINE
vec3s
glms_unprojecti(vec3s pos, mat4s invMat, vec4s vp) {
vec3s r;
glm_unprojecti(pos.raw, invMat.raw, vp.raw, r.raw);
return r;
}
/*!
* @brief maps the specified viewport coordinates into specified space [1]
* the matrix should contain projection matrix.
*
* this is same as glm_unprojecti except this function get inverse matrix for
* you.
*
* [1] space:
* 1- if m = proj: View Space
* 2- if m = viewProj: World Space
* 3- if m = MVP: Object Space
*
* You probably want to map the coordinates into object space
* so use MVP as m
*
* Computing viewProj and MVP:
* glm_mat4_mul(proj, view, viewProj);
* glm_mat4_mul(viewProj, model, MVP);
*
* @param[in] pos point/position in viewport coordinates
* @param[in] m matrix (see brief)
* @param[in] vp viewport as [x, y, width, height]
* @returns unprojected coordinates
*/
CGLM_INLINE
vec3s
glms_unproject(vec3s pos, mat4s m, vec4s vp) {
vec3s r;
glm_unproject(pos.raw, m.raw, vp.raw, r.raw);
return r;
}
/*!
* @brief map object coordinates to window coordinates
*
* Computing MVP:
* glm_mat4_mul(proj, view, viewProj);
* glm_mat4_mul(viewProj, model, MVP);
*
* @param[in] pos object coordinates
* @param[in] m MVP matrix
* @param[in] vp viewport as [x, y, width, height]
* @returns projected coordinates
*/
CGLM_INLINE
vec3s
glms_project(vec3s pos, mat4s m, vec4s vp) {
vec3s r;
glm_project(pos.raw, m.raw, vp.raw, r.raw);
return r;
}
/*!
* @brief define a picking region
*
* @param[in] center center [x, y] of a picking region in window coordinates
* @param[in] size size [width, height] of the picking region in window coordinates
* @param[in] vp viewport as [x, y, width, height]
* @returns projected coordinates
*/
CGLM_INLINE
mat4s
glms_pickmatrix(vec2s center, vec2s size, vec4s vp) {
mat4s res;
glm_pickmatrix(center.raw, size.raw, vp.raw, res.raw);
return res;
}
#endif /* cglms_projects_h */