int
gs_push_device_filter(gs_memory_t *mem, gs_state *pgs, gs_device_filter_t *df)
{
gs_device_filter_stack_t *dfs;
gx_device *new_dev = NULL;
int code;
dfs = gs_alloc_struct(mem, gs_device_filter_stack_t,
&st_gs_device_filter_stack, "gs_push_device_filter");
if (dfs == NULL)
return_error(gs_error_VMerror);
rc_increment(pgs->device);
dfs->next_device = pgs->device;
code = df->push(df, mem, pgs, &new_dev, pgs->device);
if (code < 0) {
gs_free_object(mem, dfs, "gs_push_device_filter");
return code;
}
dfs->next = pgs->dfilter_stack;
pgs->dfilter_stack = dfs;
dfs->df = df;
rc_init(dfs, mem, 1);
gs_setdevice_no_init(pgs, new_dev);
rc_decrement_only(new_dev, "gs_push_device_filter");
return code;
}
/* End a compositing operation. */
static void
end_composite(i_ctx_t *i_ctx_p, alpha_composite_state_t * pcp)
{
/* Close and free the compositor and the compositing object. */
if (pcp->cdev != pcp->orig_dev) {
gs_closedevice(pcp->cdev); /* also frees the device */
gs_setdevice_no_init(igs, pcp->orig_dev);
}
ifree_object(pcp->pcte, "end_composite(gs_composite_t)");
}
/* Begin a compositing operation. */
static int
begin_composite(i_ctx_t *i_ctx_p, alpha_composite_state_t * pcp)
{
gx_device *dev = gs_currentdevice(igs);
int code =
gs_create_composite_alpha(&pcp->pcte, &pcp->params, imemory);
if (code < 0)
return code;
pcp->orig_dev = pcp->cdev = dev; /* for end_composite */
code = (*dev_proc(dev, create_compositor))
(dev, &pcp->cdev, pcp->pcte, (gs_imager_state *)igs, imemory, NULL);
if (code < 0) {
end_composite(i_ctx_p, pcp);
return code;
}
gs_setdevice_no_init(igs, pcp->cdev);
return 0;
}
int
gs_pop_device_filter(gs_memory_t *mem, gs_state *pgs)
{
gs_device_filter_stack_t *dfs_tos = pgs->dfilter_stack;
gx_device *tos_device = pgs->device;
gs_device_filter_t *df;
int code;
if (dfs_tos == NULL)
return_error(gs_error_rangecheck);
df = dfs_tos->df;
pgs->dfilter_stack = dfs_tos->next;
code = df->prepop(df, mem, pgs, tos_device);
rc_increment(tos_device);
gs_setdevice_no_init(pgs, dfs_tos->next_device);
rc_decrement_only(dfs_tos->next_device, "gs_pop_device_filter");
dfs_tos->df = NULL;
rc_decrement_only(dfs_tos, "gs_pop_device_filter");
code = df->postpop(df, mem, pgs, tos_device);
rc_decrement_only(tos_device, "gs_pop_device_filter");
return code;
}