583 lines
15 KiB
C
583 lines
15 KiB
C
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/*
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* Copyright (c), Recep Aslantas.
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*
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* MIT License (MIT), http://opensource.org/licenses/MIT
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* Full license can be found in the LICENSE file
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*/
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/*
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Functions:
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CGLM_INLINE void glm_frustum(float left, float right,
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float bottom, float top,
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float nearVal, float farVal,
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mat4 dest)
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CGLM_INLINE void glm_ortho(float left, float right,
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float bottom, float top,
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float nearVal, float farVal,
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mat4 dest)
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CGLM_INLINE void glm_ortho_aabb(vec3 box[2], mat4 dest)
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CGLM_INLINE void glm_ortho_aabb_p(vec3 box[2], float padding, mat4 dest)
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CGLM_INLINE void glm_ortho_aabb_pz(vec3 box[2], float padding, mat4 dest)
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CGLM_INLINE void glm_ortho_default(float aspect, mat4 dest)
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CGLM_INLINE void glm_ortho_default_s(float aspect, float size, mat4 dest)
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CGLM_INLINE void glm_perspective(float fovy,
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float aspect,
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float nearVal,
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float farVal,
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mat4 dest)
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CGLM_INLINE void glm_perspective_default(float aspect, mat4 dest)
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CGLM_INLINE void glm_perspective_resize(float aspect, mat4 proj)
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CGLM_INLINE void glm_lookat(vec3 eye, vec3 center, vec3 up, mat4 dest)
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CGLM_INLINE void glm_look(vec3 eye, vec3 dir, vec3 up, mat4 dest)
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CGLM_INLINE void glm_look_anyup(vec3 eye, vec3 dir, mat4 dest)
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CGLM_INLINE void glm_persp_decomp(mat4 proj,
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float *nearVal, float *farVal,
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float *top, float *bottom,
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float *left, float *right)
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CGLM_INLINE void glm_persp_decompv(mat4 proj, float dest[6])
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CGLM_INLINE void glm_persp_decomp_x(mat4 proj, float *left, float *right)
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CGLM_INLINE void glm_persp_decomp_y(mat4 proj, float *top, float *bottom)
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CGLM_INLINE void glm_persp_decomp_z(mat4 proj, float *nearv, float *farv)
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CGLM_INLINE void glm_persp_decomp_far(mat4 proj, float *farVal)
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CGLM_INLINE void glm_persp_decomp_near(mat4 proj, float *nearVal)
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CGLM_INLINE float glm_persp_fovy(mat4 proj)
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CGLM_INLINE float glm_persp_aspect(mat4 proj)
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CGLM_INLINE void glm_persp_sizes(mat4 proj, float fovy, vec4 dest)
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*/
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#ifndef cglm_vcam_h
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#define cglm_vcam_h
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#include "common.h"
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#include "plane.h"
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/*!
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* @brief set up perspective peprojection matrix
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*
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* @param[in] left viewport.left
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* @param[in] right viewport.right
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* @param[in] bottom viewport.bottom
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* @param[in] top viewport.top
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* @param[in] nearVal near clipping plane
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* @param[in] farVal far clipping plane
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_frustum(float left, float right,
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float bottom, float top,
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float nearVal, float farVal,
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mat4 dest) {
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float rl, tb, fn, nv;
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glm_mat4_zero(dest);
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rl = 1.0f / (right - left);
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tb = 1.0f / (top - bottom);
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fn =-1.0f / (farVal - nearVal);
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nv = 2.0f * nearVal;
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dest[0][0] = nv * rl;
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dest[1][1] = nv * tb;
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dest[2][0] = (right + left) * rl;
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dest[2][1] = (top + bottom) * tb;
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dest[2][2] = (farVal + nearVal) * fn;
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dest[2][3] =-1.0f;
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dest[3][2] = farVal * nv * fn;
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}
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/*!
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* @brief set up orthographic projection matrix
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*
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* @param[in] left viewport.left
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* @param[in] right viewport.right
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* @param[in] bottom viewport.bottom
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* @param[in] top viewport.top
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* @param[in] nearVal near clipping plane
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* @param[in] farVal far clipping plane
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_ortho(float left, float right,
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float bottom, float top,
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float nearVal, float farVal,
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mat4 dest) {
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float rl, tb, fn;
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glm_mat4_zero(dest);
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rl = 1.0f / (right - left);
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tb = 1.0f / (top - bottom);
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fn =-1.0f / (farVal - nearVal);
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dest[0][0] = 2.0f * rl;
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dest[1][1] = 2.0f * tb;
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dest[2][2] = 2.0f * fn;
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dest[3][0] =-(right + left) * rl;
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dest[3][1] =-(top + bottom) * tb;
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dest[3][2] = (farVal + nearVal) * fn;
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dest[3][3] = 1.0f;
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}
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/*!
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* @brief set up orthographic projection matrix using bounding box
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*
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* bounding box (AABB) must be in view space
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*
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* @param[in] box AABB
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_ortho_aabb(vec3 box[2], mat4 dest) {
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glm_ortho(box[0][0], box[1][0],
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box[0][1], box[1][1],
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-box[1][2], -box[0][2],
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dest);
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}
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/*!
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* @brief set up orthographic projection matrix using bounding box
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*
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* bounding box (AABB) must be in view space
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*
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* @param[in] box AABB
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* @param[in] padding padding
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_ortho_aabb_p(vec3 box[2], float padding, mat4 dest) {
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glm_ortho(box[0][0] - padding, box[1][0] + padding,
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box[0][1] - padding, box[1][1] + padding,
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-(box[1][2] + padding), -(box[0][2] - padding),
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dest);
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}
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/*!
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* @brief set up orthographic projection matrix using bounding box
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*
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* bounding box (AABB) must be in view space
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*
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* @param[in] box AABB
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* @param[in] padding padding for near and far
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_ortho_aabb_pz(vec3 box[2], float padding, mat4 dest) {
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glm_ortho(box[0][0], box[1][0],
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box[0][1], box[1][1],
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-(box[1][2] + padding), -(box[0][2] - padding),
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dest);
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}
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/*!
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* @brief set up unit orthographic projection matrix
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*
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* @param[in] aspect aspect ration ( width / height )
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_ortho_default(float aspect, mat4 dest) {
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if (aspect >= 1.0f) {
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glm_ortho(-aspect, aspect, -1.0f, 1.0f, -100.0f, 100.0f, dest);
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return;
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}
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aspect = 1.0f / aspect;
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glm_ortho(-1.0f, 1.0f, -aspect, aspect, -100.0f, 100.0f, dest);
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}
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/*!
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* @brief set up orthographic projection matrix with given CUBE size
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*
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* @param[in] aspect aspect ratio ( width / height )
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* @param[in] size cube size
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_ortho_default_s(float aspect, float size, mat4 dest) {
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if (aspect >= 1.0f) {
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glm_ortho(-size * aspect,
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size * aspect,
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-size,
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size,
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-size - 100.0f,
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size + 100.0f,
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dest);
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return;
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}
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glm_ortho(-size,
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size,
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-size / aspect,
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size / aspect,
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-size - 100.0f,
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size + 100.0f,
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dest);
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}
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/*!
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* @brief set up perspective projection matrix
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*
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* @param[in] fovy field of view angle
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* @param[in] aspect aspect ratio ( width / height )
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* @param[in] nearVal near clipping plane
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* @param[in] farVal far clipping planes
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_perspective(float fovy,
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float aspect,
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float nearVal,
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float farVal,
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mat4 dest) {
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float f, fn;
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glm_mat4_zero(dest);
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f = 1.0f / tanf(fovy * 0.5f);
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fn = 1.0f / (nearVal - farVal);
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dest[0][0] = f / aspect;
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dest[1][1] = f;
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dest[2][2] = (nearVal + farVal) * fn;
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dest[2][3] =-1.0f;
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dest[3][2] = 2.0f * nearVal * farVal * fn;
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}
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/*!
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* @brief extend perspective projection matrix's far distance
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*
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* this function does not guarantee far >= near, be aware of that!
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*
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* @param[in, out] proj projection matrix to extend
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* @param[in] deltaFar distance from existing far (negative to shink)
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*/
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CGLM_INLINE
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void
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glm_persp_move_far(mat4 proj, float deltaFar) {
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float fn, farVal, nearVal, p22, p32;
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p22 = proj[2][2];
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p32 = proj[3][2];
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nearVal = p32 / (p22 - 1.0f);
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farVal = p32 / (p22 + 1.0f) + deltaFar;
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fn = 1.0f / (nearVal - farVal);
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proj[2][2] = (nearVal + farVal) * fn;
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proj[3][2] = 2.0f * nearVal * farVal * fn;
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}
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/*!
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* @brief set up perspective projection matrix with default near/far
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* and angle values
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*
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* @param[in] aspect aspect ratio ( width / height )
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_perspective_default(float aspect, mat4 dest) {
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glm_perspective(GLM_PI_4f, aspect, 0.01f, 100.0f, dest);
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}
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/*!
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* @brief resize perspective matrix by aspect ratio ( width / height )
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* this makes very easy to resize proj matrix when window /viewport
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* reized
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*
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* @param[in] aspect aspect ratio ( width / height )
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* @param[in, out] proj perspective projection matrix
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*/
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CGLM_INLINE
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void
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glm_perspective_resize(float aspect, mat4 proj) {
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if (proj[0][0] == 0.0f)
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return;
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proj[0][0] = proj[1][1] / aspect;
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}
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/*!
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* @brief set up view matrix
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*
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* NOTE: The UP vector must not be parallel to the line of sight from
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* the eye point to the reference point
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*
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* @param[in] eye eye vector
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* @param[in] center center vector
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* @param[in] up up vector
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* @param[out] dest result matrix
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*/
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CGLM_INLINE
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void
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glm_lookat(vec3 eye, vec3 center, vec3 up, mat4 dest) {
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CGLM_ALIGN(8) vec3 f, u, s;
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glm_vec3_sub(center, eye, f);
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glm_vec3_normalize(f);
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glm_vec3_crossn(f, up, s);
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glm_vec3_cross(s, f, u);
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dest[0][0] = s[0];
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dest[0][1] = u[0];
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dest[0][2] =-f[0];
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dest[1][0] = s[1];
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dest[1][1] = u[1];
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dest[1][2] =-f[1];
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dest[2][0] = s[2];
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dest[2][1] = u[2];
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dest[2][2] =-f[2];
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dest[3][0] =-glm_vec3_dot(s, eye);
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dest[3][1] =-glm_vec3_dot(u, eye);
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dest[3][2] = glm_vec3_dot(f, eye);
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dest[0][3] = dest[1][3] = dest[2][3] = 0.0f;
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dest[3][3] = 1.0f;
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}
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/*!
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* @brief set up view matrix
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*
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* convenient wrapper for lookat: if you only have direction not target self
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* then this might be useful. Because you need to get target from direction.
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*
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* NOTE: The UP vector must not be parallel to the line of sight from
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* the eye point to the reference point
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*
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* @param[in] eye eye vector
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* @param[in] dir direction vector
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||
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* @param[in] up up vector
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* @param[out] dest result matrix
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||
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*/
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CGLM_INLINE
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void
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|
|
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 */
|