From f4b8574728a5b0ac84705cd0213ca306b622eb2c Mon Sep 17 00:00:00 2001
From: Hans-Joerg Schurr <commits@schurr.at>
Date: Mon, 26 Apr 2021 22:56:57 +0200
Subject: [PATCH] Add API to inspect paths

---
 src/hvif-light.c | 36 +++++++++++++++++++++++++++++-------
 src/hvif-light.h | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 70 insertions(+), 7 deletions(-)

diff --git a/src/hvif-light.c b/src/hvif-light.c
index f595e99..2ab3ac2 100644
--- a/src/hvif-light.c
+++ b/src/hvif-light.c
@@ -3,6 +3,7 @@
 
 #include <stdint.h>
 #include <stdlib.h>
+#include <string.h>
 
 #ifdef DEBUG
 void
@@ -91,13 +92,6 @@ typedef enum hvif_line_cap
 #define MATRIX_TRANSLATION(P) \
 	(hvif_matrix) { 1.0, 0.0, 0.0, 1.0, P.x, P.y }
 
-typedef struct hvif_point hvif_point;
-struct hvif_point
-{
-	float x;
-	float y;
-};
-
 #define POINT_ORIGIN \
 	(hvif_point) { 0.0, 0.0 }
 
@@ -843,4 +837,32 @@ hvif_style_transformation(
 	return SUCCESS;
 }
 
+hvif_status hvif_path_num_points(
+	hvif_image* image, uint8_t path, uint8_t* points) {
+	if (image == NULL) return ERROR_PATH;
+	if (path >= image->num_paths) return ERROR_PATH;
+	*points = image->paths[path].num_points;
+	return SUCCESS;
+}
+
+hvif_status hvif_path_closed(
+	hvif_image* image, uint8_t path, bool* closed) {
+	if (image == NULL) return ERROR_PATH;
+	if (path >= image->num_paths) return ERROR_PATH;
+	*closed = image->paths[path].closed;
+	return SUCCESS;
+}
+
+hvif_status hvif_path_points(
+	hvif_image* image, uint8_t path, hvif_point** points) {
+	if (image == NULL) return ERROR_PATH;
+	if (path >= image->num_paths) return ERROR_PATH;
+	size_t total_points = 3 * image->paths[path].num_points;
+	hvif_point* p = calloc(total_points, sizeof(hvif_point));
+	if (!p) return ERROR_NOMEM;
+	memcpy(p, image->paths[path].points, total_points * sizeof(hvif_point));
+	*points = p;
+	return SUCCESS;
+}
+
 #endif /* INTERNAL_DATASTRUCTURES */
diff --git a/src/hvif-light.h b/src/hvif-light.h
index 24dbda2..30963b5 100644
--- a/src/hvif-light.h
+++ b/src/hvif-light.h
@@ -175,6 +175,47 @@ struct hvif_matrix
 hvif_status hvif_style_transformation(
 	hvif_image* image, uint8_t style, hvif_matrix* transformation);
 
+/**
+ * \brief Returns the number of poins in a path.
+ * \param[in] file A valid image.
+ * \param[in] path The index of the path.
+ * \param[out] points The number of points.
+ * \return ERROR_PATH if this path does not exist.
+ */
+hvif_status hvif_path_num_points(
+	hvif_image* image, uint8_t path, uint8_t* points);
+
+/**
+ * \brief Checks if the path is closed.
+ * \param[in] file A valid image.
+ * \param[in] path The index of the path.
+ * \param[out] closed If the path is a closed path.
+ * \return ERROR_PATH if this path does not exist.
+ */
+hvif_status hvif_path_closed(
+	hvif_image* image, uint8_t path, bool* closed);
+
+/** \typedef A 2D point. */
+typedef struct hvif_point hvif_point;
+struct hvif_point
+{
+	float x;
+	float y;
+};
+
+/**
+ * \brief Returns a copy of the poins in a path including the control points.
+ * \param[in] file A valid image.
+ * \param[in] path The index of the path.
+ * \param[out] points The points and control points.
+ * \return ERROR_PATH if this path does not exist. ERROR_NOMEM if points
+ *         list could not be allocated.
+ * \remark There are two control point per point. Hence the length
+ *         of the  array is 3 * num_points.
+ */
+hvif_status hvif_path_points(
+	hvif_image* image, uint8_t path, hvif_point** points);
+
 /**@}*/
 
 #endif /* HVIF_LIGHT_H */