compositor: Use libpng directly instead of gdb-pixbuf

compositor/Makefile.am

@@ -38,6 +38,7 @@ endif
 compositor_SOURCES =				\
 	compositor.c				\
 	compositor.h				\
+	image-loader.c				\
 	shell.c					\
 	switcher.c				\
 	screenshooter.c				\

compositor/compositor-x11.c

@@ -240,12 +240,13 @@ struct wm_normal_hints {
 #define WM_NORMAL_HINTS_MAX_SIZE	32
 
 static void
-x11_output_set_icon(struct x11_compositor *c, struct x11_output *output,
+x11_output_set_icon(struct x11_compositor *c,
-		    const char *filename, int width, int height)
+		    struct x11_output *output, const char *filename)
 {
-	uint32_t *icon, *pixels;
+	uint32_t *icon, *pixels, stride;
+	int32_t width, height;
 
-	pixels = wlsc_load_image(filename, width, height);
+	pixels = wlsc_load_image(filename, &width, &height, &stride);
 	if (!pixels)
 		return;
 	icon = malloc(width * height * 4 + 8);
@@ -332,8 +333,7 @@ x11_compositor_create_output(struct x11_compositor *c, int width, int height)
 			    c->atom.wm_class, c->atom.string, 8,
 			    sizeof class, class);
 
-	x11_output_set_icon(c, output,
+	x11_output_set_icon(c, output, DATADIR "/wayland/wayland.png");
-			    DATADIR "/wayland/wayland.png", 128, 128);
 
 	xcb_map_window(c->conn, output->window);
 

compositor/compositor.c

@@ -260,73 +260,6 @@ destroy_surface(struct wl_resource *resource, struct wl_client *client)
 	free(surface);
 }
 
-uint32_t *
-wlsc_load_image(const char *filename, int width, int height)
-{
-	GdkPixbuf *pixbuf;
-	GError *error = NULL;
-	int stride, i, n_channels;
-	unsigned char *pixels, *end, *argb_pixels, *s, *d;
-
-	pixbuf = gdk_pixbuf_new_from_file_at_scale(filename,
-						   width, height,
-						   FALSE, &error);
-	if (error != NULL) {
-		fprintf(stderr, "failed to load image: %s\n", error->message);
-		g_error_free(error);
-		return NULL;
-	}
-
-	stride = gdk_pixbuf_get_rowstride(pixbuf);
-	pixels = gdk_pixbuf_get_pixels(pixbuf);
-	n_channels = gdk_pixbuf_get_n_channels(pixbuf);
-
-	argb_pixels = malloc (height * width * 4);
-	if (argb_pixels == NULL) {
-		g_object_unref(pixbuf);
-		return NULL;
-	}
-
-	if (n_channels == 4) {
-		for (i = 0; i < height; i++) {
-			s = pixels + i * stride;
-			end = s + width * 4;
-			d = argb_pixels + i * width * 4;
-			while (s < end) {
-				unsigned int t;
-
-#define MULT(_d,c,a,t) \
-	do { t = c * a + 0x7f; _d = ((t >> 8) + t) >> 8; } while (0)
-				
-				MULT(d[0], s[2], s[3], t);
-				MULT(d[1], s[1], s[3], t);
-				MULT(d[2], s[0], s[3], t);
-				d[3] = s[3];
-				s += 4;
-				d += 4;
-			}
-		}
-	} else if (n_channels == 3) {
-		for (i = 0; i < height; i++) {
-			s = pixels + i * stride;
-			end = s + width * 3;
-			d = argb_pixels + i * width * 4;
-			while (s < end) {
-				d[0] = s[2];
-				d[1] = s[1];
-				d[2] = s[0];
-				d[3] = 0xff;
-				s += 3;
-				d += 4;
-			}
-		}
-	}
-
-	g_object_unref(pixbuf);
-
-	return (uint32_t *) argb_pixels;
-}
-
 static void
 wlsc_buffer_attach(struct wl_buffer *buffer, struct wl_surface *surface)
 {
@@ -393,13 +326,14 @@ enum sprite_usage {
 
 static struct wlsc_sprite *
 create_sprite_from_png(struct wlsc_compositor *ec,
-		       const char *filename, int width, int height,
+		       const char *filename, uint32_t usage)
-		       uint32_t usage)
 {
 	uint32_t *pixels;
 	struct wlsc_sprite *sprite;
+	int32_t width, height;
+	uint32_t stride;
 
-	pixels = wlsc_load_image(filename, width, height);
+	pixels = wlsc_load_image(filename, &width, &height, &stride);
 	if (pixels == NULL)
 		return NULL;
 
@@ -459,7 +393,6 @@ static void
 create_pointer_images(struct wlsc_compositor *ec)
 {
 	int i, count;
-	const int width = 32, height = 32;
 
 	count = ARRAY_LENGTH(pointer_images);
 	ec->pointer_sprites = malloc(count * sizeof *ec->pointer_sprites);
@@ -467,7 +400,6 @@ create_pointer_images(struct wlsc_compositor *ec)
 		ec->pointer_sprites[i] =
 			create_sprite_from_png(ec,
 					       pointer_images[i].filename,
-					       width, height,
 					       SPRITE_USE_CURSOR);
 	}
 }
@@ -484,8 +416,7 @@ background_create(struct wlsc_output *output, const char *filename)
 	if (background == NULL)
 		return NULL;
 
-	sprite = create_sprite_from_png(output->compositor, filename,
+	sprite = create_sprite_from_png(output->compositor, filename, 0);
-					output->width, output->height, 0);
 	if (sprite == NULL) {
 		free(background);
 		return NULL;

compositor/compositor.h

@@ -357,6 +357,7 @@ void
 screenshooter_create(struct wlsc_compositor *ec);
 
 uint32_t *
-wlsc_load_image(const char *filename, int width, int height);
+wlsc_load_image(const char *filename,
+		int32_t *width_arg, int32_t *height_arg, uint32_t *stride_arg);
 
 #endif

compositor/image-loader.c

@@ -0,0 +1,176 @@
+/*
+ * Copyright © 2011 Intel Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and
+ * its documentation for any purpose is hereby granted without fee, provided
+ * that the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of the copyright holders not be used in
+ * advertising or publicity pertaining to distribution of the software
+ * without specific, written prior permission.  The copyright holders make
+ * no representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+ * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
+ * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <errno.h>
+#include <png.h>
+
+#include "compositor.h"
+
+static inline int
+multiply_alpha(int alpha, int color)
+{
+    int temp = (alpha * color) + 0x80;
+
+    return ((temp + (temp >> 8)) >> 8);
+}
+
+static void
+premultiply_data(png_structp   png,
+		 png_row_infop row_info,
+		 png_bytep     data)
+{
+    unsigned int i;
+    png_bytep p;
+
+    for (i = 0, p = data; i < row_info->rowbytes; i += 4, p += 4) {
+	png_byte  alpha = p[3];
+	uint32_t w;
+
+	if (alpha == 0) {
+		w = 0;
+	} else {
+		png_byte red   = p[0];
+		png_byte green = p[1];
+		png_byte blue  = p[2];
+
+		if (alpha != 0xff) {
+			red   = multiply_alpha(alpha, red);
+			green = multiply_alpha(alpha, green);
+			blue  = multiply_alpha(alpha, blue);
+		}
+		w = (alpha << 24) | (red << 16) | (green << 8) | (blue << 0);
+	}
+
+	* (uint32_t *) p = w;
+    }
+}
+
+static void
+read_func(png_structp png, png_bytep data, png_size_t size)
+{
+	FILE *fp = png_get_io_ptr(png);
+
+	if (fread(data, 1, size, fp) < 0)
+		png_error(png, NULL);
+}
+
+uint32_t *
+wlsc_load_image(const char *filename,
+		int32_t *width_arg, int32_t *height_arg, uint32_t *stride_arg)
+{
+	png_struct *png;
+	png_info *info;
+	png_byte *data;
+	png_byte **row_pointers = NULL;
+	png_uint_32 width, height;
+	int depth, color_type, interlace, stride;
+	unsigned int i;
+	FILE *fp;
+
+	fp = fopen(filename, "rb");
+	if (fp == NULL)
+		return NULL;
+
+	png = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+				     NULL, NULL, NULL);
+	if (!png) {
+		fclose(fp);
+		return NULL;
+	}
+
+	info = png_create_info_struct(png);
+	if (!info) {
+		png_destroy_read_struct(&png, &info, NULL);
+		fclose(fp);
+		return NULL;
+	}
+
+	png_set_read_fn(png, fp, read_func);
+	png_read_info(png, info);
+	png_get_IHDR(png, info,
+		     &width, &height, &depth,
+		     &color_type, &interlace, NULL, NULL);
+
+	if (color_type == PNG_COLOR_TYPE_PALETTE)
+		png_set_palette_to_rgb(png);
+
+	if (color_type == PNG_COLOR_TYPE_GRAY)
+		png_set_expand_gray_1_2_4_to_8(png);
+
+	if (png_get_valid(png, info, PNG_INFO_tRNS))
+		png_set_tRNS_to_alpha(png);
+
+	if (depth == 16)
+		png_set_strip_16(png);
+
+	if (depth < 8)
+		png_set_packing(png);
+
+	if (color_type == PNG_COLOR_TYPE_GRAY ||
+	    color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+		png_set_gray_to_rgb(png);
+
+	if (interlace != PNG_INTERLACE_NONE)
+		png_set_interlace_handling(png);
+
+	png_set_filler(png, 0xff, PNG_FILLER_AFTER);
+	png_set_read_user_transform_fn(png, premultiply_data);
+	png_read_update_info(png, info);
+	png_get_IHDR(png, info,
+		     &width, &height, &depth,
+		     &color_type, &interlace, NULL, NULL);
+
+	stride = width * 4;
+	data = malloc(stride * height);
+	if (!data) {
+		png_destroy_read_struct(&png, &info, NULL);
+		fclose(fp);
+		return NULL;
+	}
+
+	row_pointers = malloc(height * sizeof row_pointers[0]);
+	if (row_pointers == NULL) {
+		free(data);
+		png_destroy_read_struct(&png, &info, NULL);
+		fclose(fp);
+		return NULL;
+	}
+
+	for (i = 0; i < height; i++)
+		row_pointers[i] = &data[i * stride];
+
+	png_read_image(png, row_pointers);
+	png_read_end(png, info);
+
+	free(row_pointers);
+	png_destroy_read_struct(&png, &info, NULL);
+	fclose(fp);
+
+	*width_arg = width;
+	*height_arg = height;
+	*stride_arg = stride;
+
+	return (uint32_t *) data;
+}