1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
|
/**
* $Id$
*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* 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 the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Contributor(s): Willian P. Germano, Campbell Barton
*
* ***** END GPL LICENSE BLOCK *****
*/
/* ****************************************** */
/* Drivers - PyExpression Evaluation */
#include <Python.h>
#include "DNA_anim_types.h"
#include "BLI_listbase.h"
#include "BLI_math_base.h"
#include "BKE_fcurve.h"
#include "BKE_global.h"
/* for pydrivers (drivers using one-line Python expressions to express relationships between targets) */
PyObject *bpy_pydriver_Dict = NULL;
/* For faster execution we keep a special dictionary for pydrivers, with
* the needed modules and aliases.
*/
int bpy_pydriver_create_dict(void)
{
PyObject *d, *mod;
/* validate namespace for driver evaluation */
if (bpy_pydriver_Dict) return -1;
d = PyDict_New();
if (d == NULL)
return -1;
else
bpy_pydriver_Dict = d;
/* import some modules: builtins, bpy, math, (Blender.noise )*/
PyDict_SetItemString(d, "__builtins__", PyEval_GetBuiltins());
mod = PyImport_ImportModule("math");
if (mod) {
PyDict_Merge(d, PyModule_GetDict(mod), 0); /* 0 - dont overwrite existing values */
Py_DECREF(mod);
}
/* add bpy to global namespace */
mod= PyImport_ImportModuleLevel((char *)"bpy", NULL, NULL, NULL, 0);
if (mod) {
PyDict_SetItemString(bpy_pydriver_Dict, "bpy", mod);
Py_DECREF(mod);
}
#if 0 // non existant yet
mod = PyImport_ImportModule("Blender.Noise");
if (mod) {
PyDict_SetItemString(d, "noise", mod);
PyDict_SetItemString(d, "n", mod);
Py_DECREF(mod);
} else {
PyErr_Clear();
}
/* If there's a Blender text called pydrivers.py, import it.
* Users can add their own functions to this module.
*/
if (G.f & G_SCRIPT_AUTOEXEC) {
mod = importText("pydrivers"); /* can also use PyImport_Import() */
if (mod) {
PyDict_SetItemString(d, "pydrivers", mod);
PyDict_SetItemString(d, "p", mod);
Py_DECREF(mod);
} else {
PyErr_Clear();
}
}
#endif // non existant yet
return 0;
}
/* Update function, it gets rid of pydrivers global dictionary, forcing
* BPY_eval_driver to recreate it. This function is used to force
* reloading the Blender text module "pydrivers.py", if available, so
* updates in it reach pydriver evaluation.
*/
void BPY_reset_driver(void)
{
PyGILState_STATE gilstate;
int use_gil= 1; // (PyThreadState_Get()==NULL);
if(use_gil)
gilstate = PyGILState_Ensure();
if (bpy_pydriver_Dict) { /* free the global dict used by pydrivers */
PyDict_Clear(bpy_pydriver_Dict);
Py_DECREF(bpy_pydriver_Dict);
bpy_pydriver_Dict = NULL;
}
if(use_gil)
PyGILState_Release(gilstate);
return;
}
/* error return function for BPY_eval_pydriver */
static void pydriver_error(ChannelDriver *driver)
{
driver->flag |= DRIVER_FLAG_INVALID; /* py expression failed */
fprintf(stderr, "\nError in Driver: The following Python expression failed:\n\t'%s'\n\n", driver->expression);
// BPy_errors_to_report(NULL); // TODO - reports
PyErr_Print();
PyErr_Clear();
}
/* This evals py driver expressions, 'expr' is a Python expression that
* should evaluate to a float number, which is returned.
*
* note: PyGILState_Ensure() isnt always called because python can call the
* bake operator which intern starts a thread which calls scene update which
* does a driver update. to avoid a deadlock check PyThreadState_Get() if PyGILState_Ensure() is needed.
*/
float BPY_eval_driver (ChannelDriver *driver)
{
PyObject *driver_vars=NULL;
PyObject *retval= NULL;
PyObject *expr_vars; /* speed up by pre-hashing string & avoids re-converting unicode strings for every execution */
PyObject *expr_code;
PyGILState_STATE gilstate;
int use_gil;
DriverVar *dvar;
double result = 0.0; /* default return */
char *expr = NULL;
short targets_ok= 1;
int i;
/* get the py expression to be evaluated */
expr = driver->expression;
if ((expr == NULL) || (expr[0]=='\0'))
return 0.0f;
if(!(G.f & G_SCRIPT_AUTOEXEC)) {
printf("skipping driver '%s', automatic scripts are disabled\n", driver->expression);
return 0.0f;
}
use_gil= 1; //(PyThreadState_Get()==NULL);
if(use_gil)
gilstate = PyGILState_Ensure();
/* init global dictionary for py-driver evaluation settings */
if (!bpy_pydriver_Dict) {
if (bpy_pydriver_create_dict() != 0) {
fprintf(stderr, "Pydriver error: couldn't create Python dictionary");
if(use_gil)
PyGILState_Release(gilstate);
return 0.0f;
}
}
if(driver->expr_comp==NULL)
driver->flag |= DRIVER_FLAG_RECOMPILE;
/* compile the expression first if it hasn't been compiled or needs to be rebuilt */
if(driver->flag & DRIVER_FLAG_RECOMPILE) {
Py_XDECREF(driver->expr_comp);
driver->expr_comp= PyTuple_New(2);
expr_code= Py_CompileString(expr, "<bpy driver>", Py_eval_input);
PyTuple_SET_ITEM(((PyObject *)driver->expr_comp), 0, expr_code);
driver->flag &= ~DRIVER_FLAG_RECOMPILE;
driver->flag |= DRIVER_FLAG_RENAMEVAR; /* maybe this can be removed but for now best keep until were sure */
}
else {
expr_code= PyTuple_GET_ITEM(((PyObject *)driver->expr_comp), 0);
}
if(driver->flag & DRIVER_FLAG_RENAMEVAR) {
/* may not be set */
expr_vars= PyTuple_GET_ITEM(((PyObject *)driver->expr_comp), 1);
Py_XDECREF(expr_vars);
/* intern the arg names so creating the namespace for every run is faster */
expr_vars= PyTuple_New(BLI_countlist(&driver->variables));
PyTuple_SET_ITEM(((PyObject *)driver->expr_comp), 1, expr_vars);
for (dvar= driver->variables.first, i=0; dvar; dvar= dvar->next) {
PyTuple_SET_ITEM(expr_vars, i++, PyUnicode_InternFromString(dvar->name));
}
driver->flag &= ~DRIVER_FLAG_RENAMEVAR;
}
else {
expr_vars= PyTuple_GET_ITEM(((PyObject *)driver->expr_comp), 1);
}
/* add target values to a dict that will be used as '__locals__' dict */
driver_vars = PyDict_New(); // XXX do we need to decref this?
for (dvar= driver->variables.first, i=0; dvar; dvar= dvar->next) {
PyObject *driver_arg = NULL;
float tval = 0.0f;
/* try to get variable value */
tval= driver_get_variable_value(driver, dvar);
driver_arg= PyFloat_FromDouble((double)tval);
/* try to add to dictionary */
/* if (PyDict_SetItemString(driver_vars, dvar->name, driver_arg)) { */
if (PyDict_SetItem(driver_vars, PyTuple_GET_ITEM(expr_vars, i++), driver_arg) < 0) { /* use string interning for faster namespace creation */
/* this target failed - bad name */
if (targets_ok) {
/* first one - print some extra info for easier identification */
fprintf(stderr, "\nBPY_eval_driver() - Error while evaluating PyDriver:\n");
targets_ok= 0;
}
fprintf(stderr, "\tBPY_eval_driver() - couldn't add variable '%s' to namespace\n", dvar->name);
// BPy_errors_to_report(NULL); // TODO - reports
PyErr_Print();
PyErr_Clear();
}
}
#if 0 // slow, with this can avoid all Py_CompileString above.
/* execute expression to get a value */
retval = PyRun_String(expr, Py_eval_input, bpy_pydriver_Dict, driver_vars);
#else
/* evaluate the compiled expression */
if (expr_code)
retval= PyEval_EvalCode((PyCodeObject *)expr_code, bpy_pydriver_Dict, driver_vars);
#endif
/* decref the driver vars first... */
Py_DECREF(driver_vars);
/* process the result */
if (retval == NULL) {
pydriver_error(driver);
} else if((result= PyFloat_AsDouble(retval)) == -1.0 && PyErr_Occurred()) {
pydriver_error(driver);
Py_DECREF(retval);
result = 0.0;
}
else {
/* all fine, make sure the "invalid expression" flag is cleared */
driver->flag &= ~DRIVER_FLAG_INVALID;
Py_DECREF(retval);
}
if(use_gil)
PyGILState_Release(gilstate);
if(finite(result)) {
return (float)result;
}
else {
fprintf(stderr, "\tBPY_eval_driver() - driver '%s' evaluates to '%f'\n", dvar->name, result);
return 0.0f;
}
}
|