quakeforge/libs/scene/transform.c
Bill Currie 35eec0b2e5 [ecs] Implement hierarchies as components
The main goal of this change was to make it easier to tell when a
hierarchy has been deleted, but as a side benefit, it got rid of the use
of PR_RESMAP. Also, it's easy to track the number of hierarchies.

Unfortunately, it showed how brittle the component side of the ECS is
(scene and canvas registries assumed their components were the first (no
long the case), thus the sweeping changes).

Centerprint doesn't work (but it hasn't for a while).
2024-01-02 16:38:01 +09:00

393 lines
12 KiB
C

/*
transform.c
General transform handling
Copyright (C) 2021 Bill Currke
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#define IMPLEMENT_TRANSFORM_Funcs
#include "QF/scene/scene.h"
#include "QF/scene/transform.h"
static void
transform_mat4f_identity (void *_mat)
{
vec4f_t *mat = _mat;
mat4fidentity (mat);
}
static void
transform_rotation_identity (void *_rot)
{
vec4f_t *rot = _rot;
*rot = (vec4f_t) { 0, 0, 0, 1 };
}
static void
transform_scale_identity (void *_scale)
{
vec4f_t *scale = _scale;
*scale = (vec4f_t) { 1, 1, 1, 1 };
}
static void
transform_modified_init (void *_modified)
{
byte *modified = _modified;
*modified = 1;
}
static const component_t transform_components[transform_type_count] = {
[transform_type_name] = {
.size = sizeof (char *),
.name = "Name",
},
[transform_type_tag] = {
.size = sizeof (uint32_t),
.name = "Tag",
},
[transform_type_modified] = {
.size = sizeof (byte),
.create = transform_modified_init,
.name = "Modified",
},
[transform_type_localMatrix] = {
.size = sizeof (mat4f_t),
.create = transform_mat4f_identity,
.name = "Local Matrix",
},
[transform_type_localInverse] = {
.size = sizeof (mat4f_t),
.create = transform_mat4f_identity,
.name = "Local Inverse",
},
[transform_type_worldMatrix] = {
.size = sizeof (mat4f_t),
.create = transform_mat4f_identity,
.name = "World Matrix",
},
[transform_type_worldInverse] = {
.size = sizeof (mat4f_t),
.create = transform_mat4f_identity,
.name = "World Inverse",
},
[transform_type_localRotation] = {
.size = sizeof (vec4f_t),
.create = transform_rotation_identity,
.name = "Local Rotation",
},
[transform_type_localScale] = {
.size = sizeof (vec4f_t),
.create = transform_scale_identity,
.name = "Local Scale",
},
[transform_type_worldRotation] = {
.size = sizeof (vec4f_t),
.create = transform_rotation_identity,
.name = "World Rotation",
},
};
static const hierarchy_type_t transform_type = {
.num_components = transform_type_count,
.components = transform_components,
};
static void
transform_calcLocalInverse (hierarchy_t *h, uint32_t index)
{
mat4f_t *localMatrix = h->components[transform_type_localMatrix];
mat4f_t *localInverse = h->components[transform_type_localInverse];
// This takes advantage of the fact that localMatrix is a simple
// homogenous scale/rotate/translate matrix with no shear
vec4f_t x = localMatrix[index][0];
vec4f_t y = localMatrix[index][1];
vec4f_t z = localMatrix[index][2];
vec4f_t t = localMatrix[index][3];
// "one" is to ensure both the scalar and translation have 1 in their
// fourth components
vec4f_t one = { 0, 0, 0, 1 };
vec4f_t nx = { x[0], y[0], z[0], 0 };
vec4f_t ny = { x[1], y[1], z[1], 0 };
vec4f_t nz = { x[2], y[2], z[2], 0 };
vec4f_t nt = one - t[0] * nx - t[1] * ny - t[2] * nz;
// vertical dot product!!!
vec4f_t s = 1 / (nx * nx + ny * ny + nz * nz + one);
localInverse[index][0] = nx * s;
localInverse[index][1] = ny * s;
localInverse[index][2] = nz * s;
localInverse[index][3] = nt * s;
}
static void
Transform_UpdateMatrices (hierarchy_t *h)
{
mat4f_t *localMatrix = h->components[transform_type_localMatrix];
mat4f_t *localInverse = h->components[transform_type_localInverse];
mat4f_t *worldMatrix = h->components[transform_type_worldMatrix];
mat4f_t *worldInverse = h->components[transform_type_worldInverse];
vec4f_t *localRotation = h->components[transform_type_localRotation];
vec4f_t *worldRotation = h->components[transform_type_worldRotation];
byte *modified = h->components[transform_type_modified];
for (uint32_t i = 0; i < h->num_objects; i++) {
if (modified[i]) {
transform_calcLocalInverse (h, i);
}
}
if (modified[0]) {
memcpy (worldMatrix[0],
localMatrix[0], sizeof (mat4_t));
memcpy (worldInverse[0],
localInverse[0], sizeof (mat4_t));
worldRotation[0] = localRotation[0];
}
for (size_t i = 1; i < h->num_objects; i++) {
uint32_t parent = h->parentIndex[i];
if (modified[i] || modified[parent]) {
mmulf (worldMatrix[i],
worldMatrix[parent], localMatrix[i]);
modified[i] = 1;
}
}
for (size_t i = 1; i < h->num_objects; i++) {
uint32_t parent = h->parentIndex[i];
if (modified[i] || modified[parent]) {
mmulf (worldInverse[i],
localInverse[i], worldInverse[parent]);
}
}
for (size_t i = 1; i < h->num_objects; i++) {
uint32_t parent = h->parentIndex[i];
if (modified[i] || modified[parent]) {
worldRotation[i] = qmulf (worldRotation[parent],
localRotation[i]);
}
}
memset (modified, 0, h->num_objects);
}
transform_t
Transform_New (ecs_system_t ssys, transform_t parent)
{
uint32_t transform = ECS_NewEntity (ssys.reg);
hierref_t *ref = Ent_AddComponent (transform, ssys.base + scene_href,
ssys.reg);
if (parent.reg && parent.id != nullent) {
hierref_t pref = Transform_GetRef (parent);
*ref = Hierarchy_InsertHierarchy (pref, nullhref, ssys.reg);
} else {
ref->id = Hierarchy_New (ssys.reg, ssys.base + scene_href,
&transform_type, 1);
ref->index = 0;
}
hierarchy_t *h = Ent_GetComponent (ref->id, ecs_hierarchy, ssys.reg);
h->ent[ref->index] = transform;
Transform_UpdateMatrices (h);
return (transform_t) {
.reg = ssys.reg,
.id = transform,
.comp = ssys.base + scene_href,
};
}
void
Transform_Delete (transform_t transform)
{
hierref_t ref = Transform_GetRef (transform);
if (ref.index != 0) {
// The transform is not the root, so pull it out of its current
// hierarchy so deleting it is easier
Transform_SetParent (transform, (transform_t) {});
}
// Takes care of freeing the transforms
Hierarchy_Delete (ref.id, transform.reg);
}
transform_t
Transform_NewNamed (ecs_system_t ssys, transform_t parent, const char *name)
{
transform_t transform = Transform_New (ssys, parent);
Transform_SetName (transform, name);
return transform;
}
void
Transform_SetParent (transform_t transform, transform_t parent)
{
hierref_t dref = nullhref;
hierref_t sref = Transform_GetRef (transform);
if (Transform_Valid (parent)) {
dref = Transform_GetRef (parent);
}
Hierarchy_SetParent (dref, sref, transform.reg);
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
byte *modified = h->components[transform_type_modified];
modified[ref.index] = 1;
Transform_UpdateMatrices (h);
}
void
Transform_SetName (transform_t transform, const char *_name)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
char **name = h->components[transform_type_name];
//FIXME create a string pool (similar to qfcc's, or even move that to util)
if (name[ref.index]) {
free (name[ref.index]);
}
name[ref.index] = strdup (_name);
}
void
Transform_SetTag (transform_t transform, uint32_t _tag)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
uint32_t *tag = h->components[transform_type_tag];
tag[ref.index] = _tag;
}
void
Transform_SetLocalPosition (transform_t transform, vec4f_t position)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
mat4f_t *localMatrix = h->components[transform_type_localMatrix];
byte *modified = h->components[transform_type_modified];
localMatrix[ref.index][3] = position;
modified[ref.index] = 1;
Transform_UpdateMatrices (h);
}
void
Transform_SetLocalRotation (transform_t transform, vec4f_t rotation)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
mat4f_t *localMatrix = h->components[transform_type_localMatrix];
vec4f_t *localRotation = h->components[transform_type_localRotation];
vec4f_t *localScale = h->components[transform_type_localScale];
byte *modified = h->components[transform_type_modified];
vec4f_t scale = localScale[ref.index];
mat4f_t mat;
mat4fquat (mat, rotation);
localRotation[ref.index] = rotation;
localMatrix[ref.index][0] = mat[0] * scale[0];
localMatrix[ref.index][1] = mat[1] * scale[1];
localMatrix[ref.index][2] = mat[2] * scale[2];
modified[ref.index] = 1;
Transform_UpdateMatrices (h);
}
void
Transform_SetLocalScale (transform_t transform, vec4f_t scale)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
mat4f_t *localMatrix = h->components[transform_type_localMatrix];
vec4f_t *localRotation = h->components[transform_type_localRotation];
vec4f_t *localScale = h->components[transform_type_localScale];
byte *modified = h->components[transform_type_modified];
vec4f_t rotation = localRotation[ref.index];
mat4f_t mat;
mat4fquat (mat, rotation);
localScale[ref.index] = scale;
localMatrix[ref.index][0] = mat[0] * scale[0];
localMatrix[ref.index][1] = mat[1] * scale[1];
localMatrix[ref.index][2] = mat[2] * scale[2];
modified[ref.index] = 1;
Transform_UpdateMatrices (h);
}
void
Transform_SetWorldPosition (transform_t transform, vec4f_t position)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
if (ref.index) {
mat4f_t *worldInverse = h->components[transform_type_worldInverse];
uint32_t parent = h->parentIndex[ref.index];
position = mvmulf (worldInverse[parent], position);
}
Transform_SetLocalPosition (transform, position);
}
void
Transform_SetWorldRotation (transform_t transform, vec4f_t rotation)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
if (ref.index) {
vec4f_t *worldRotation = h->components[transform_type_worldRotation];
uint32_t parent = h->parentIndex[ref.index];
rotation = qmulf (qconjf (worldRotation[parent]), rotation);
}
Transform_SetLocalRotation (transform, rotation);
}
void
Transform_SetLocalTransform (transform_t transform, vec4f_t scale,
vec4f_t rotation, vec4f_t position)
{
auto ref = Transform_GetRef (transform);
hierarchy_t *h = Ent_GetComponent (ref.id, ecs_hierarchy, transform.reg);
mat4f_t *localMatrix = h->components[transform_type_localMatrix];
vec4f_t *localRotation = h->components[transform_type_localRotation];
vec4f_t *localScale = h->components[transform_type_localScale];
byte *modified = h->components[transform_type_modified];
mat4f_t mat;
mat4fquat (mat, rotation);
position[3] = 1;
localRotation[ref.index] = rotation;
localScale[ref.index] = scale;
localMatrix[ref.index][0] = mat[0] * scale[0];
localMatrix[ref.index][1] = mat[1] * scale[1];
localMatrix[ref.index][2] = mat[2] * scale[2];
localMatrix[ref.index][3] = position;
modified[ref.index] = 1;
Transform_UpdateMatrices (h);
}