Switch back to Cairo for drawing selection

meson.build

@@ -43,6 +43,7 @@ add_project_arguments(cc.get_supported_arguments([
 wayland_client = dependency('wayland-client')
 wayland_protos = dependency('wayland-protocols')
 
+cairo = dependency('cairo')
 pixman = dependency('pixman-1')
 spng = dependency('spng', fallback: 'libspng')
 xkbcommon = dependency(
@@ -75,6 +76,7 @@ executable(
   dependencies: [
     client_protos,
     wayland_client,
+    cairo,
     pixman,
     spng,
     xkbcommon,

src/config.c

@@ -10,10 +10,9 @@
 
 #define CONFIG_SUBPATH "dulcepan.cfg"
 
-static void bytes_to_color(uint8_t bytes[static 4], float out[static 4]) {
-	out[3] = (float)bytes[3] / UINT8_MAX;
-	for (size_t i = 0; i < 3; i++) {
-		out[i] = (float)bytes[i] * out[3] / UINT8_MAX;
+static inline void bytes_to_color(uint8_t bytes[static 4], float out[static 4]) {
+	for (size_t i = 0; i < 4; i++) {
+		out[i] = (float)bytes[i] / UINT8_MAX;
 	}
 }
 

src/dulcepan.h

@@ -1,7 +1,7 @@
 #ifndef DULCEPAN_H
 #define DULCEPAN_H
 
-#include <pixman.h>
+#include <cairo.h>
 #include <stdbool.h>
 #include <stddef.h>
 #include <wayland-util.h>
@@ -18,7 +18,8 @@ enum dp_status {
 
 struct dp_buffer {
 	struct wl_buffer *wl_buffer;
-	pixman_image_t *image;
+	cairo_t *cairo;
+	cairo_surface_t *cairo_surface;
 	void *data;
 	size_t size;
 	bool used;
@@ -123,6 +124,7 @@ enum dp_file_format {
 };
 
 struct dp_config {
+	// RGBA, not premultiplied
 	float unselected_color[4];
 	float selected_color[4];
 	float border_color[4];
@@ -161,10 +163,6 @@ struct dp_state {
 	enum dp_file_format output_format;
 
 	bool show_cursors;
-
-	pixman_image_t *unselected_fill_image;
-	pixman_image_t *selected_fill_image;
-	pixman_image_t *border_fill_image;
 };
 
 void dp_config_load(struct dp_config *config, const char *user_path);

src/main.c

@@ -166,16 +166,6 @@ static void help(const char *prog) {
 			prog);
 }
 
-static pixman_image_t *make_image(float color[static 4]) {
-	pixman_color_t pixman_color = {
-		.red = (uint16_t)(color[0] * UINT16_MAX),
-		.green = (uint16_t)(color[1] * UINT16_MAX),
-		.blue = (uint16_t)(color[2] * UINT16_MAX),
-		.alpha = (uint16_t)(color[3] * UINT16_MAX),
-	};
-	return pixman_image_create_solid_fill(&pixman_color);
-}
-
 int main(int argc, char **argv) {
 	struct dp_state state = {0};
 
@@ -233,16 +223,8 @@ int main(int argc, char **argv) {
 		dp_log_fatal("Failed to connect to a Wayland compositor");
 	}
 
-	state.unselected_fill_image = make_image(state.config.unselected_color);
-	state.selected_fill_image = make_image(state.config.selected_color);
-	state.border_fill_image = make_image(state.config.border_color);
-
 	run(&state);
 
-	pixman_image_unref(state.unselected_fill_image);
-	pixman_image_unref(state.selected_fill_image);
-	pixman_image_unref(state.border_fill_image);
-
 	xkb_context_unref(state.xkb_context);
 
 	wl_display_disconnect(state.display);

src/output.c

@@ -208,8 +208,9 @@ static void output_handle_done(void *data, struct wl_output *wl_output) {
 		buffer->wl_buffer =
 				dp_buffer_create(state, output->transformed_width, output->transformed_height,
 						stride, WL_SHM_FORMAT_ARGB8888, &buffer->data, &buffer->size);
-		buffer->image = pixman_image_create_bits(PIXMAN_a8r8g8b8, output->transformed_width,
-				output->transformed_height, buffer->data, stride);
+		buffer->cairo_surface = cairo_image_surface_create_for_data(buffer->data,
+				CAIRO_FORMAT_ARGB32, output->transformed_width, output->transformed_height, stride);
+		buffer->cairo = cairo_create(buffer->cairo_surface);
 
 		wl_buffer_add_listener(buffer->wl_buffer, &buffer_listener, buffer);
 	}
@@ -242,6 +243,10 @@ static const struct wl_callback_listener redraw_callback_listener = {
 	.done = redraw_callback_handle_done,
 };
 
+static inline void set_cairo_color(cairo_t *cairo, float color[static 4]) {
+	cairo_set_source_rgba(cairo, color[0], color[1], color[2], color[3]);
+}
+
 static void redraw(struct dp_output *output) {
 	assert(output->redraw_callback == NULL);
 
@@ -260,30 +265,29 @@ static void redraw(struct dp_output *output) {
 	buffer->used = true;
 
 	struct dp_state *state = output->state;
+	struct dp_config *config = &state->config;
 
-	pixman_image_composite32(PIXMAN_OP_SRC, state->unselected_fill_image, NULL, buffer->image, 0, 0,
-			0, 0, 0, 0, output->transformed_width, output->transformed_height);
+	cairo_set_operator(buffer->cairo, CAIRO_OPERATOR_SOURCE);
+
+	set_cairo_color(buffer->cairo, config->unselected_color);
+	cairo_paint(buffer->cairo);
 
 	struct dp_selection *selection = &state->selection;
 	if (output == selection->output) {
-		int border_size = state->config.border_size;
+		int border_size = config->border_size;
 		if (border_size != 0) {
-			pixman_image_composite32(PIXMAN_OP_SRC, state->border_fill_image, NULL, buffer->image,
-					0, 0, 0, 0, selection->x - border_size, selection->y - border_size,
-					selection->width + border_size * 2, border_size);
-			pixman_image_composite32(PIXMAN_OP_SRC, state->border_fill_image, NULL, buffer->image,
-					0, 0, 0, 0, selection->x - border_size, selection->y + selection->height,
-					selection->width + border_size * 2, border_size);
-			pixman_image_composite32(PIXMAN_OP_SRC, state->border_fill_image, NULL, buffer->image,
-					0, 0, 0, 0, selection->x - border_size, selection->y, border_size,
-					selection->height);
-			pixman_image_composite32(PIXMAN_OP_SRC, state->border_fill_image, NULL, buffer->image,
-					0, 0, 0, 0, selection->x + selection->width, selection->y, border_size,
-					selection->height);
+			cairo_set_line_width(buffer->cairo, border_size);
+			double off = border_size / 2.0;
+			cairo_rectangle(buffer->cairo, selection->x - off, selection->y - off,
+					selection->width + border_size, selection->height + border_size);
+			set_cairo_color(buffer->cairo, config->border_color);
+			cairo_stroke(buffer->cairo);
 		}
 
-		pixman_image_composite32(PIXMAN_OP_SRC, state->selected_fill_image, NULL, buffer->image, 0,
-				0, 0, 0, selection->x, selection->y, selection->width, selection->height);
+		cairo_rectangle(
+				buffer->cairo, selection->x, selection->y, selection->width, selection->height);
+		set_cairo_color(buffer->cairo, config->selected_color);
+		cairo_fill(buffer->cairo);
 	}
 
 	wl_surface_attach(output->select_surface, buffer->wl_buffer, 0, 0);
@@ -335,7 +339,8 @@ void dp_output_destroy(struct dp_output *output) {
 	for (size_t i = 0; i < DP_SWAPCHAIN_LEN; i++) {
 		struct dp_buffer *buffer = &output->swapchain[i];
 		wl_buffer_destroy(buffer->wl_buffer);
-		pixman_image_unref(buffer->image);
+		cairo_destroy(buffer->cairo);
+		cairo_surface_destroy(buffer->cairo_surface);
 		munmap(buffer->data, buffer->size);
 	}
 

src/save.c

@@ -1,4 +1,5 @@
 #include <errno.h>
+#include <pixman.h>
 #include <spng.h>
 #include <stdio.h>
 #include <stdlib.h>