1 files changed, 70 insertions, 0 deletions
diff --git a/lib/hitomezashi.h b/lib/hitomezashi.h
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+++ b/lib/hitomezashi.h
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+/** @file */
+
+#ifndef HITOMEZASHI_HITOMEZASHI_H
+#define HITOMEZASHI_HITOMEZASHI_H
+
+#include "SDL.h"
+
+/** The state of a hitomezashi pattern.
+ */
+struct Hitomezashi_State {
+  /** The length of the x_pattern. */
+  int x_pattern_len;
+  /** The length of the y_pattern. */
+  int y_pattern_len;
+
+  /** Pattern used to draw the vertical lines conceptually originating from the
+   * x axis. This is an array of 0s and 1s.
+   */
+  char *x_pattern;
+  /** Pattern used to draw the horizontal lines conceptually originating from
+   * the y axis. This is an array of 0s and 1s.
+   */
+  char *y_pattern;
+
+  /** Gap between parallel lines. */
+  int gap;
+
+  /** Thickness of each line. */
+  int line_thickness;
+
+  /** Width in pixels of the SDL_Surface needed to hold the pattern. This is
+   * calculated by hitomezashi_state_init(). */
+  int output_width;
+  /** Height in pixels of the SDL_Surface needed to hold the pattern. This is
+   * calculated by hitomezashi_state_init(). */
+  int output_height;
+
+  /** SDL_Surface the pattern is drawn to by hitomezashi_draw(). */
+  SDL_Surface *surface;
+};
+
+/** Result of hitomezashi_state_init(). */
+enum Hitomezashi_State_Init_Result {
+  /** The function completed successfully. */
+  Hitomezashi_State_Init_Result_Success,
+  /** The function failed as it encountered an error initialising the
+     SDL_Surface in state. */
+  Hitomezashi_State_Init_Result_Err_Create_Surface,
+};
+
+/** Result of hitomezashi_draw() */
+enum Hitomezashi_Draw_Result {
+  /** The function completed successfully. */
+  Hitomezashi_Draw_Result_Success,
+  /** The function failed as it encountered an error "locking" the surface to
+     write to it. */
+  Hitomezashi_Draw_Result_Err_Lock_Surface,
+};
+
+/** Initialise a Hitomezashi_State struct so that it is ready to be passed to
+ * hitomezashi_draw(). */
+enum Hitomezashi_State_Init_Result
+hitomezashi_state_init(struct Hitomezashi_State *state, int x_pattern_len,
+                       int y_pattern_len, char *x_pattern, char *y_pattern,
+                       int gap, int line_thickness);
+
+/** Draw the hitomezashi pattern to a Hitomezashi_State's surface. */
+enum Hitomezashi_Draw_Result hitomezashi_draw(struct Hitomezashi_State *state);
+
+#endif // HITOMEZASHI_HITOMEZASHI_H