78 lines
1.9 KiB
C
78 lines
1.9 KiB
C
#include "../graph.h"
|
|
#include "../module_registry.h"
|
|
|
|
typedef struct {
|
|
GraphNode as_GraphNode;
|
|
int64_t previous;
|
|
} DifferentiateGraphNode;
|
|
|
|
static bool
|
|
handle_event(EventPositionBase * self, EventNode * event)
|
|
{
|
|
DifferentiateGraphNode *node = DOWNCAST(DifferentiateGraphNode, GraphNode, DOWNCAST(GraphNode, EventPositionBase, self));
|
|
size_t count = node->as_GraphNode.outputs.length;
|
|
if (!count) {
|
|
event_destroy(event);
|
|
return true;
|
|
}
|
|
|
|
int64_t current = event->data.payload;
|
|
event->data.payload = current - node->previous;
|
|
node->previous = current;
|
|
|
|
graph_node_broadcast_forward_event(&node->as_GraphNode, event);
|
|
return true;
|
|
}
|
|
|
|
static GraphNode *
|
|
create(GraphNodeSpecification * spec, GraphNodeConfig * config, InitializationEnvironment * env)
|
|
{
|
|
(void) config;
|
|
(void) env;
|
|
DifferentiateGraphNode * node = T_ALLOC(1, DifferentiateGraphNode);
|
|
if (!node) {
|
|
return NULL;
|
|
}
|
|
|
|
int64_t initial = 0;
|
|
if (config->options) {
|
|
initial = env_resolve_constant(env, config_setting_get_member(config->options, "initial"));
|
|
}
|
|
|
|
*node = (DifferentiateGraphNode) {
|
|
.as_GraphNode = {
|
|
.as_EventPositionBase = {
|
|
.handle_event = &handle_event,
|
|
.waiting_new_event = false,
|
|
},
|
|
.specification = spec,
|
|
.inputs = EMPTY_GRAPH_CHANNEL_LIST,
|
|
.outputs = EMPTY_GRAPH_CHANNEL_LIST,
|
|
},
|
|
.previous = initial,
|
|
};
|
|
return &node->as_GraphNode;
|
|
}
|
|
|
|
static void destroy
|
|
(GraphNodeSpecification * self, GraphNode * target)
|
|
{
|
|
(void) self;
|
|
free(target);
|
|
}
|
|
|
|
GraphNodeSpecification nodespec_differentiate = (GraphNodeSpecification) {
|
|
.create = &create,
|
|
.destroy = &destroy,
|
|
.register_io = NULL,
|
|
.name = "differentiate",
|
|
.documentation = "Subtracts the previous event payload from the current one\nAccepts events on any connector\nSends events on all connectors"
|
|
"\nOption 'initial' (optional): the value to subtract from the first event payload"
|
|
,
|
|
};
|
|
|
|
MODULE_CONSTRUCTOR(init)
|
|
{
|
|
register_graph_node_specification(&nodespec_differentiate);
|
|
}
|