godot/core/math/camera_matrix.cpp
Rémi Verschelde d8223ffa75 Welcome in 2017, dear changelog reader!
That year should bring the long-awaited OpenGL ES 3.0 compatible renderer
with state-of-the-art rendering techniques tuned to work as low as middle
end handheld devices - without compromising with the possibilities given
for higher end desktop games of course. Great times ahead for the Godot
community and the gamers that will play our games!

(cherry picked from commit c7bc44d5ad)
2017-01-12 19:15:30 +01:00

615 lines
16 KiB
C++

/*************************************************************************/
/* camera_matrix.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#include "camera_matrix.h"
#include "math_funcs.h"
#include "print_string.h"
void CameraMatrix::set_identity() {
for (int i=0;i<4;i++) {
for (int j=0;j<4;j++) {
matrix[i][j]=(i==j)?1:0;
}
}
}
void CameraMatrix::set_zero() {
for (int i=0;i<4;i++) {
for (int j=0;j<4;j++) {
matrix[i][j]=0;
}
}
}
Plane CameraMatrix::xform4(const Plane& p_vec4) {
Plane ret;
ret.normal.x = matrix[0][0] * p_vec4.normal.x + matrix[1][0] * p_vec4.normal.y + matrix[2][0] * p_vec4.normal.z + matrix[3][0] * p_vec4.d;
ret.normal.y = matrix[0][1] * p_vec4.normal.x + matrix[1][1] * p_vec4.normal.y + matrix[2][1] * p_vec4.normal.z + matrix[3][1] * p_vec4.d;
ret.normal.z = matrix[0][2] * p_vec4.normal.x + matrix[1][2] * p_vec4.normal.y + matrix[2][2] * p_vec4.normal.z + matrix[3][2] * p_vec4.d;
ret.d = matrix[0][3] * p_vec4.normal.x + matrix[1][3] * p_vec4.normal.y + matrix[2][3] * p_vec4.normal.z + matrix[3][3] * p_vec4.d;
return ret;
}
void CameraMatrix::set_perspective(float p_fovy_degrees, float p_aspect, float p_z_near, float p_z_far,bool p_flip_fov) {
if (p_flip_fov) {
p_fovy_degrees=get_fovy(p_fovy_degrees,1.0/p_aspect);
}
float sine, cotangent, deltaZ;
float radians = p_fovy_degrees / 2.0 * Math_PI / 180.0;
deltaZ = p_z_far - p_z_near;
sine = Math::sin(radians);
if ((deltaZ == 0) || (sine == 0) || (p_aspect == 0)) {
return ;
}
cotangent = Math::cos(radians) / sine;
set_identity();
matrix[0][0] = cotangent / p_aspect;
matrix[1][1] = cotangent;
matrix[2][2] = -(p_z_far + p_z_near) / deltaZ;
matrix[2][3] = -1;
matrix[3][2] = -2 * p_z_near * p_z_far / deltaZ;
matrix[3][3] = 0;
}
void CameraMatrix::set_orthogonal(float p_left, float p_right, float p_bottom, float p_top, float p_znear, float p_zfar) {
set_identity();
matrix[0][0] = 2.0/(p_right-p_left);
matrix[3][0] = -((p_right+p_left)/(p_right-p_left));
matrix[1][1] = 2.0/(p_top-p_bottom);
matrix[3][1] = -((p_top+p_bottom)/(p_top-p_bottom));
matrix[2][2] = -2.0/(p_zfar-p_znear);
matrix[3][2] = -((p_zfar+p_znear)/(p_zfar-p_znear));
matrix[3][3] = 1.0;
}
void CameraMatrix::set_orthogonal(float p_size, float p_aspect, float p_znear, float p_zfar,bool p_flip_fov) {
if (!p_flip_fov) {
p_size*=p_aspect;
}
set_orthogonal(-p_size/2,+p_size/2,-p_size/p_aspect/2,+p_size/p_aspect/2,p_znear,p_zfar);
}
void CameraMatrix::set_frustum(float p_left, float p_right, float p_bottom, float p_top, float p_near, float p_far) {
#if 0
///@TODO, give a check to this. I'm not sure if it's working.
set_identity();
matrix[0][0]=(2*p_near) / (p_right-p_left);
matrix[0][2]=(p_right+p_left) / (p_right-p_left);
matrix[1][1]=(2*p_near) / (p_top-p_bottom);
matrix[1][2]=(p_top+p_bottom) / (p_top-p_bottom);
matrix[2][2]=-(p_far+p_near) / ( p_far-p_near);
matrix[2][3]=-(2*p_far*p_near) / (p_far-p_near);
matrix[3][2]=-1;
matrix[3][3]=0;
#else
float *te = &matrix[0][0];
float x = 2 * p_near / ( p_right - p_left );
float y = 2 * p_near / ( p_top - p_bottom );
float a = ( p_right + p_left ) / ( p_right - p_left );
float b = ( p_top + p_bottom ) / ( p_top - p_bottom );
float c = - ( p_far + p_near ) / ( p_far - p_near );
float d = - 2 * p_far * p_near / ( p_far - p_near );
te[0] = x; te[4] = 0; te[8] = a; te[12] = 0;
te[1] = 0; te[5] = y; te[9] = b; te[13] = 0;
te[2] = 0; te[6] = 0; te[10] = c; te[14] = d;
te[3] = 0; te[7] = 0; te[11] = - 1; te[15] = 0;
#endif
}
float CameraMatrix::get_z_far() const {
const float * matrix = (const float*)this->matrix;
Plane new_plane=Plane(matrix[ 3] - matrix[ 2],
matrix[ 7] - matrix[ 6],
matrix[11] - matrix[10],
matrix[15] - matrix[14]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
return new_plane.d;
}
float CameraMatrix::get_z_near() const {
const float * matrix = (const float*)this->matrix;
Plane new_plane=Plane(matrix[ 3] + matrix[ 2],
matrix[ 7] + matrix[ 6],
matrix[11] + matrix[10],
-matrix[15] - matrix[14]);
new_plane.normalize();
return new_plane.d;
}
void CameraMatrix::get_viewport_size(float& r_width, float& r_height) const {
const float * matrix = (const float*)this->matrix;
///////--- Near Plane ---///////
Plane near_plane=Plane(matrix[ 3] + matrix[ 2],
matrix[ 7] + matrix[ 6],
matrix[11] + matrix[10],
-matrix[15] - matrix[14]).normalized();
///////--- Right Plane ---///////
Plane right_plane=Plane(matrix[ 3] - matrix[ 0],
matrix[ 7] - matrix[ 4],
matrix[11] - matrix[ 8],
- matrix[15] + matrix[12]).normalized();
Plane top_plane=Plane(matrix[ 3] - matrix[ 1],
matrix[ 7] - matrix[ 5],
matrix[11] - matrix[ 9],
-matrix[15] + matrix[13]).normalized();
Vector3 res;
near_plane.intersect_3(right_plane,top_plane,&res);
r_width=res.x;
r_height=res.y;
}
bool CameraMatrix::get_endpoints(const Transform& p_transform, Vector3 *p_8points) const {
const float * matrix = (const float*)this->matrix;
///////--- Near Plane ---///////
Plane near_plane=Plane(matrix[ 3] + matrix[ 2],
matrix[ 7] + matrix[ 6],
matrix[11] + matrix[10],
-matrix[15] - matrix[14]).normalized();
///////--- Far Plane ---///////
Plane far_plane=Plane(matrix[ 2] - matrix[ 3],
matrix[ 6] - matrix[ 7],
matrix[10] - matrix[11],
matrix[15] - matrix[14]).normalized();
///////--- Right Plane ---///////
Plane right_plane=Plane(matrix[ 0] - matrix[ 3],
matrix[ 4] - matrix[ 7],
matrix[8] - matrix[ 11],
- matrix[15] + matrix[12]).normalized();
///////--- Top Plane ---///////
Plane top_plane=Plane(matrix[ 1] - matrix[ 3],
matrix[ 5] - matrix[ 7],
matrix[9] - matrix[ 11],
-matrix[15] + matrix[13]).normalized();
Vector3 near_endpoint;
Vector3 far_endpoint;
bool res=near_plane.intersect_3(right_plane,top_plane,&near_endpoint);
ERR_FAIL_COND_V(!res,false);
res=far_plane.intersect_3(right_plane,top_plane,&far_endpoint);
ERR_FAIL_COND_V(!res,false);
p_8points[0]=p_transform.xform( Vector3( near_endpoint.x, near_endpoint.y, near_endpoint.z ) );
p_8points[1]=p_transform.xform( Vector3( near_endpoint.x,-near_endpoint.y, near_endpoint.z ) );
p_8points[2]=p_transform.xform( Vector3(-near_endpoint.x, near_endpoint.y, near_endpoint.z ) );
p_8points[3]=p_transform.xform( Vector3(-near_endpoint.x,-near_endpoint.y, near_endpoint.z ) );
p_8points[4]=p_transform.xform( Vector3( far_endpoint.x, far_endpoint.y, far_endpoint.z ) );
p_8points[5]=p_transform.xform( Vector3( far_endpoint.x,-far_endpoint.y, far_endpoint.z ) );
p_8points[6]=p_transform.xform( Vector3(-far_endpoint.x, far_endpoint.y, far_endpoint.z ) );
p_8points[7]=p_transform.xform( Vector3(-far_endpoint.x,-far_endpoint.y, far_endpoint.z ) );
return true;
}
Vector<Plane> CameraMatrix::get_projection_planes(const Transform& p_transform) const {
/** Fast Plane Extraction from combined modelview/projection matrices.
* References:
* http://www.markmorley.com/opengl/frustumculling.html
* http://www2.ravensoft.com/users/ggribb/plane%20extraction.pdf
*/
Vector<Plane> planes;
const float * matrix = (const float*)this->matrix;
Plane new_plane;
///////--- Near Plane ---///////
new_plane=Plane(matrix[ 3] + matrix[ 2],
matrix[ 7] + matrix[ 6],
matrix[11] + matrix[10],
matrix[15] + matrix[14]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
planes.push_back( p_transform.xform(new_plane) );
///////--- Far Plane ---///////
new_plane=Plane(matrix[ 3] - matrix[ 2],
matrix[ 7] - matrix[ 6],
matrix[11] - matrix[10],
matrix[15] - matrix[14]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
planes.push_back( p_transform.xform(new_plane) );
///////--- Left Plane ---///////
new_plane=Plane(matrix[ 3] + matrix[ 0],
matrix[ 7] + matrix[ 4],
matrix[11] + matrix[ 8],
matrix[15] + matrix[12]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
planes.push_back( p_transform.xform(new_plane) );
///////--- Top Plane ---///////
new_plane=Plane(matrix[ 3] - matrix[ 1],
matrix[ 7] - matrix[ 5],
matrix[11] - matrix[ 9],
matrix[15] - matrix[13]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
planes.push_back( p_transform.xform(new_plane) );
///////--- Right Plane ---///////
new_plane=Plane(matrix[ 3] - matrix[ 0],
matrix[ 7] - matrix[ 4],
matrix[11] - matrix[ 8],
matrix[15] - matrix[12]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
planes.push_back( p_transform.xform(new_plane) );
///////--- Bottom Plane ---///////
new_plane=Plane(matrix[ 3] + matrix[ 1],
matrix[ 7] + matrix[ 5],
matrix[11] + matrix[ 9],
matrix[15] + matrix[13]);
new_plane.normal=-new_plane.normal;
new_plane.normalize();
planes.push_back( p_transform.xform(new_plane) );
return planes;
}
CameraMatrix CameraMatrix::inverse() const {
CameraMatrix cm = *this;
cm.invert();
return cm;
}
void CameraMatrix::invert() {
int i,j,k;
int pvt_i[4], pvt_j[4]; /* Locations of pivot matrix */
float pvt_val; /* Value of current pivot element */
float hold; /* Temporary storage */
float determinat; /* Determinant */
determinat = 1.0;
for (k=0; k<4; k++) {
/** Locate k'th pivot element **/
pvt_val=matrix[k][k]; /** Initialize for search **/
pvt_i[k]=k;
pvt_j[k]=k;
for (i=k; i<4; i++) {
for (j=k; j<4; j++) {
if (Math::absd(matrix[i][j]) > Math::absd(pvt_val)) {
pvt_i[k]=i;
pvt_j[k]=j;
pvt_val=matrix[i][j];
}
}
}
/** Product of pivots, gives determinant when finished **/
determinat*=pvt_val;
if (Math::absd(determinat)<1e-7) {
return; //(false); /** Matrix is singular (zero determinant). **/
}
/** "Interchange" rows (with sign change stuff) **/
i=pvt_i[k];
if (i!=k) { /** If rows are different **/
for (j=0; j<4; j++) {
hold=-matrix[k][j];
matrix[k][j]=matrix[i][j];
matrix[i][j]=hold;
}
}
/** "Interchange" columns **/
j=pvt_j[k];
if (j!=k) { /** If columns are different **/
for (i=0; i<4; i++) {
hold=-matrix[i][k];
matrix[i][k]=matrix[i][j];
matrix[i][j]=hold;
}
}
/** Divide column by minus pivot value **/
for (i=0; i<4; i++) {
if (i!=k) matrix[i][k]/=( -pvt_val) ;
}
/** Reduce the matrix **/
for (i=0; i<4; i++) {
hold = matrix[i][k];
for (j=0; j<4; j++) {
if (i!=k && j!=k) matrix[i][j]+=hold*matrix[k][j];
}
}
/** Divide row by pivot **/
for (j=0; j<4; j++) {
if (j!=k) matrix[k][j]/=pvt_val;
}
/** Replace pivot by reciprocal (at last we can touch it). **/
matrix[k][k] = 1.0/pvt_val;
}
/* That was most of the work, one final pass of row/column interchange */
/* to finish */
for (k=4-2; k>=0; k--) { /* Don't need to work with 1 by 1 corner*/
i=pvt_j[k]; /* Rows to swap correspond to pivot COLUMN */
if (i!=k) { /* If rows are different */
for(j=0; j<4; j++) {
hold = matrix[k][j];
matrix[k][j]=-matrix[i][j];
matrix[i][j]=hold;
}
}
j=pvt_i[k]; /* Columns to swap correspond to pivot ROW */
if (j!=k) /* If columns are different */
for (i=0; i<4; i++) {
hold=matrix[i][k];
matrix[i][k]=-matrix[i][j];
matrix[i][j]=hold;
}
}
}
CameraMatrix::CameraMatrix() {
set_identity();
}
CameraMatrix CameraMatrix::operator*(const CameraMatrix& p_matrix) const {
CameraMatrix new_matrix;
for( int j = 0; j < 4; j++ ) {
for( int i = 0; i < 4; i++ ) {
real_t ab = 0;
for( int k = 0; k < 4; k++ )
ab += matrix[k][i] * p_matrix.matrix[j][k] ;
new_matrix.matrix[j][i] = ab;
}
}
return new_matrix;
}
void CameraMatrix::set_light_bias() {
float *m=&matrix[0][0];
m[0]=0.5,
m[1]=0.0,
m[2]=0.0,
m[3]=0.0,
m[4]=0.0,
m[5]=0.5,
m[6]=0.0,
m[7]=0.0,
m[8]=0.0,
m[9]=0.0,
m[10]=0.5,
m[11]=0.0,
m[12]=0.5,
m[13]=0.5,
m[14]=0.5,
m[15]=1.0;
}
CameraMatrix::operator String() const {
String str;
for (int i=0;i<4;i++)
for (int j=0;j<4;j++)
str+=String((j>0)?", ":"\n")+rtos(matrix[i][j]);
return str;
}
float CameraMatrix::get_aspect() const {
float w,h;
get_viewport_size(w,h);
return w/h;
}
float CameraMatrix::get_fov() const {
const float * matrix = (const float*)this->matrix;
Plane right_plane=Plane(matrix[ 3] - matrix[ 0],
matrix[ 7] - matrix[ 4],
matrix[11] - matrix[ 8],
- matrix[15] + matrix[12]).normalized();
return Math::rad2deg(Math::acos(Math::abs(right_plane.normal.x)))*2.0;
}
void CameraMatrix::make_scale(const Vector3 &p_scale) {
set_identity();
matrix[0][0]=p_scale.x;
matrix[1][1]=p_scale.y;
matrix[2][2]=p_scale.z;
}
void CameraMatrix::scale_translate_to_fit(const AABB& p_aabb) {
Vector3 min = p_aabb.pos;
Vector3 max = p_aabb.pos+p_aabb.size;
matrix[0][0]=2/(max.x-min.x);
matrix[1][0]=0;
matrix[2][0]=0;
matrix[3][0]=-(max.x+min.x)/(max.x-min.x);
matrix[0][1]=0;
matrix[1][1]=2/(max.y-min.y);
matrix[2][1]=0;
matrix[3][1]=-(max.y+min.y)/(max.y-min.y);
matrix[0][2]=0;
matrix[1][2]=0;
matrix[2][2]=2/(max.z-min.z);
matrix[3][2]=-(max.z+min.z)/(max.z-min.z);
matrix[0][3]=0;
matrix[1][3]=0;
matrix[2][3]=0;
matrix[3][3]=1;
}
CameraMatrix::operator Transform() const {
Transform tr;
const float *m=&matrix[0][0];
tr.basis.elements[0][0]=m[0];
tr.basis.elements[1][0]=m[1];
tr.basis.elements[2][0]=m[2];
tr.basis.elements[0][1]=m[4];
tr.basis.elements[1][1]=m[5];
tr.basis.elements[2][1]=m[6];
tr.basis.elements[0][2]=m[8];
tr.basis.elements[1][2]=m[9];
tr.basis.elements[2][2]=m[10];
tr.origin.x=m[12];
tr.origin.y=m[13];
tr.origin.z=m[14];
return tr;
}
CameraMatrix::CameraMatrix(const Transform& p_transform) {
const Transform &tr = p_transform;
float *m=&matrix[0][0];
m[0]=tr.basis.elements[0][0];
m[1]=tr.basis.elements[1][0];
m[2]=tr.basis.elements[2][0];
m[3]=0.0;
m[4]=tr.basis.elements[0][1];
m[5]=tr.basis.elements[1][1];
m[6]=tr.basis.elements[2][1];
m[7]=0.0;
m[8]=tr.basis.elements[0][2];
m[9]=tr.basis.elements[1][2];
m[10]=tr.basis.elements[2][2];
m[11]=0.0;
m[12]=tr.origin.x;
m[13]=tr.origin.y;
m[14]=tr.origin.z;
m[15]=1.0;
}
CameraMatrix::~CameraMatrix()
{
}