Add fancy borders

src/dulcepan.h

@@ -8,6 +8,10 @@
 #include <wayland-util.h>
 #include <xkbcommon/xkbcommon.h>
 
+#define DP_PI 3.14159265358979323846
+// sqrt(2) / 2
+#define DP_SQRT2_2 0.7071067811865476
+
 // Per-output
 #define DP_SWAPCHAIN_LEN 2
 
@@ -128,14 +132,28 @@ enum dp_file_format {
 	DP_FILE_PPM,
 };
 
+enum dp_border_gradient {
+	DP_BORDER_GRADIENT_NONE,
+	DP_BORDER_GRADIENT_LINEAR,
+	DP_BORDER_GRADIENT_LOOP,
+};
+
 struct dp_config {
 	// RGBA, not premultiplied
 	float unselected_color[4];
 	float selected_color[4];
 	float border_color[4];
+	float border_secondary_color[4];
+
 	xkb_keysym_t quit_key;
 	xkb_keysym_t save_key;
+
 	int border_size; // 0 if disabled
+	enum dp_border_gradient border_gradient;
+	double gradient_angle; // In radians
+	int loop_step;
+	int animation_duration; // In milliseconds
+
 	int png_compression;
 	bool quick_select;
 };
@@ -172,6 +190,11 @@ struct dp_state {
 	enum dp_file_format output_format;
 
 	bool show_cursors;
+
+	cairo_pattern_t *border_pattern;
+	cairo_matrix_t precomputed_linear_matrix;
+	double loop_step_scale;
+	double time_multiplier;
 };
 
 void dp_config_load(struct dp_state *state, const char *user_path);
@@ -207,6 +230,8 @@ void dp_log_fatal(const char *fmt, ...);
 void *dp_zalloc(size_t size);
 char *dp_strdup(const char *str);
 
+void dp_matrix_compute_linear(cairo_matrix_t *matrix, double angle);
+
 const char *dp_ext_from_path(const char *path);
 enum dp_file_format dp_ext_to_format(const char *ext);