MSYS2: add a comment about realpath

on_app_activate() currently makes use of the CWD we are launched with,
so I'm choosing to not enforce it globally.

README.adoc

@@ -13,7 +13,7 @@ Features
    photos, HEIC, AVIF, SVG, X11 cursors and TIFF, or whatever your gdk-pixbuf
    modules manage to load.
  - Employs high-performance file format libraries: Wuffs and libjpeg-turbo.
- - Makes use of 30-bit X.org visuals, whenever it's possible and appropriate.
+ - Can make use of 30-bit X.org visuals, under certain conditions.
  - Has a notion of pages, and tries to load all included content within files.
  - Can keep the zoom and position when browsing, to help with comparing
    zoomed-in images.
@@ -38,12 +38,15 @@ You can get a package with the latest development version using Arch Linux's
 https://aur.archlinux.org/packages/fiv-git[AUR],
 or as a https://git.janouch.name/p/nixexprs[Nix derivation].
 
+https://janouch.name/cd[Windows installers can be found here],
+you want the _x86_64_ version.
+
 Building and Running
 --------------------
 Build-only dependencies:
  Meson, pkg-config, asciidoctor or asciidoc (recommended but optional) +
 Runtime dependencies: gtk+-3.0, glib>=2.64, pixman-1, shared-mime-info,
- libturbojpeg, libwebp, librsvg-2.0 (for icons) +
+ libturbojpeg, libwebp, libepoxy, librsvg-2.0 (for icons) +
 Optional dependencies: lcms2, Little CMS fast float plugin,
  LibRaw, librsvg-2.0, xcursor, libheif, libtiff, ExifTool,
  resvg (unstable API, needs to be requested explicitly) +

docs/fiv.html

@@ -16,7 +16,7 @@ q:lang(en):after { content: "’"; }
 <p class="details">
 <span id="author">Přemysl Eric Janouch</span><br>
 <span id="email"><a href="mailto:p@janouch.name">p@janouch.name</a></span><br>
-<span id="revnumber">version 0.0.0,</span>
+<span id="revnumber">version 1.0.0,</span>
 <span id="revdate">2023-04-17</span>
 
 <p class="figure"><img src="fiv.webp" alt="fiv in browser and viewer modes">

fiv-browser.c

@@ -1,7 +1,7 @@
 //
 // fiv-browser.c: filesystem browsing widget
 //
-// Copyright (c) 2021 - 2024, Přemysl Eric Janouch <p@janouch.name>
+// Copyright (c) 2021 - 2025, Přemysl Eric Janouch <p@janouch.name>
 //
 // Permission to use, copy, modify, and/or distribute this software for any
 // purpose with or without fee is hereby granted.
@@ -828,9 +828,18 @@ thumbnailer_next(Thumbnailer *t)
 		"--thumbnail", fiv_thumbnail_sizes[self->item_size].thumbnail_spec_name,
 		"--", uri, NULL};
 
+	GSubprocessLauncher *launcher =
+		g_subprocess_launcher_new(G_SUBPROCESS_FLAGS_STDOUT_PIPE);
+#ifdef G_OS_WIN32
+	gchar *prefix = g_win32_get_package_installation_directory_of_module(NULL);
+	g_subprocess_launcher_set_cwd(launcher, prefix);
+	g_free(prefix);
+#endif
+
 	GError *error = NULL;
-	t->minion = g_subprocess_newv(t->target->icon ? argv_faster : argv_slower,
-		G_SUBPROCESS_FLAGS_STDOUT_PIPE, &error);
+	t->minion = g_subprocess_launcher_spawnv(
+		launcher, t->target->icon ? argv_faster : argv_slower, &error);
+	g_object_unref(launcher);
 	if (error) {
 		g_warning("%s", error->message);
 		g_error_free(error);
@@ -1314,10 +1323,14 @@ fiv_browser_button_release_event(GtkWidget *widget, GdkEventButton *event)
 	if (!entry || entry != entry_at(self, event->x, event->y))
 		return GDK_EVENT_PROPAGATE;
 
+	GdkModifierType primary = gdk_keymap_get_modifier_mask(
+		gdk_keymap_get_for_display(gtk_widget_get_display(widget)),
+		GDK_MODIFIER_INTENT_PRIMARY_ACCELERATOR);
+
 	guint state = event->state & gtk_accelerator_get_default_mod_mask();
 	if ((event->button == GDK_BUTTON_PRIMARY && state == 0))
 		return open_entry(widget, entry, FALSE);
-	if ((event->button == GDK_BUTTON_PRIMARY && state == GDK_CONTROL_MASK) ||
+	if ((event->button == GDK_BUTTON_PRIMARY && state == primary) ||
 		(event->button == GDK_BUTTON_MIDDLE && state == 0))
 		return open_entry(widget, entry, TRUE);
 	return GDK_EVENT_PROPAGATE;

fiv-context-menu.c

@@ -185,15 +185,24 @@ info_spawn(GtkWidget *dialog, const char *path, GBytes *bytes_in)
 	if (bytes_in)
 		flags |= G_SUBPROCESS_FLAGS_STDIN_PIPE;
 
+	GSubprocessLauncher *launcher = g_subprocess_launcher_new(flags);
+#ifdef G_OS_WIN32
+	// Both to find wperl, and then to let wperl find the nearby exiftool.
+	gchar *prefix = g_win32_get_package_installation_directory_of_module(NULL);
+	g_subprocess_launcher_set_cwd(launcher, prefix);
+	g_free(prefix);
+#endif
+
 	// TODO(p): Add a fallback to internal capabilities.
 	// The simplest is to specify the filename and the resolution.
 	GError *error = NULL;
-	GSubprocess *subprocess = g_subprocess_new(flags, &error,
+	GSubprocess *subprocess = g_subprocess_launcher_spawn(launcher, &error,
 #ifdef G_OS_WIN32
 		"wperl",
 #endif
 		"exiftool", "-tab", "-groupNames", "-duplicates", "-extractEmbedded",
 		"--binary", "-quiet", "--", path, NULL);
+	g_object_unref(launcher);
 	if (error) {
 		info_redirect_error(dialog, error);
 		return;

fiv-io-cmm.c

@@ -400,7 +400,8 @@ fiv_io_cmm_argb32_premultiply(FivIoCmm *self,
 #else  // ! HAVE_LCMS2 || LCMS_VERSION < 2130
 
 static void
-fiv_io_cmm_argb32(FivIoCmm *, FivIoImage *, FivIoProfile *, FivIoProfile *)
+fiv_io_cmm_argb32(G_GNUC_UNUSED FivIoCmm *self, G_GNUC_UNUSED FivIoImage *image,
+	G_GNUC_UNUSED FivIoProfile *source, G_GNUC_UNUSED FivIoProfile *target)
 {
 	// TODO(p): Unpremultiply, transform, repremultiply. Or require lcms2>=2.13.
 }

fiv-io-model.c

@@ -247,7 +247,9 @@ static GPtrArray *
 model_decide_placement(
 	FivIoModel *self, GFileInfo *info, GPtrArray *subdirs, GPtrArray *files)
 {
-	if (self->filtering && g_file_info_get_is_hidden(info))
+	if (self->filtering &&
+		g_file_info_has_attribute(info, G_FILE_ATTRIBUTE_STANDARD_IS_HIDDEN) &&
+		g_file_info_get_is_hidden(info))
 		return NULL;
 	if (g_file_info_get_file_type(info) == G_FILE_TYPE_DIRECTORY)
 		return subdirs;
@@ -380,6 +382,9 @@ on_monitor_changed(G_GNUC_UNUSED GFileMonitor *monitor, GFile *file,
 	switch (event_type) {
 	case G_FILE_MONITOR_EVENT_CHANGED:
 	case G_FILE_MONITOR_EVENT_ATTRIBUTE_CHANGED:
+		// On macOS, we seem to not receive _CHANGED for child files.
+		// And while this seems to arrive too early, it's a mild improvement.
+	case G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT:
 		event = MONITOR_CHANGING;
 		new_entry_file = file;
 		break;
@@ -398,8 +403,6 @@ on_monitor_changed(G_GNUC_UNUSED GFileMonitor *monitor, GFile *file,
 		new_entry_file = file;
 		break;
 
-	case G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT:
-		// TODO(p): Figure out if we can't make use of _CHANGES_DONE_HINT.
 	case G_FILE_MONITOR_EVENT_PRE_UNMOUNT:
 	case G_FILE_MONITOR_EVENT_UNMOUNTED:
 		// TODO(p): Figure out how to handle _UNMOUNTED sensibly.

fiv-io.c

@@ -42,6 +42,8 @@
 #include <libraw.h>
 #if LIBRAW_VERSION >= LIBRAW_MAKE_VERSION(0, 21, 0)
 #define LIBRAW_OPIONS_NO_MEMERR_CALLBACK 0
+#else
+#define rawparams params
 #endif
 #endif  // HAVE_LIBRAW
 #ifdef HAVE_RESVG
@@ -59,6 +61,9 @@
 #ifdef HAVE_LIBTIFF
 #include <tiff.h>
 #include <tiffio.h>
+#ifndef TIFF_TMSIZE_T_MAX
+#define TIFF_TMSIZE_T_MAX ((tmsize_t) (SIZE_MAX >> 1))
+#endif
 #endif  // HAVE_LIBTIFF
 #ifdef HAVE_GDKPIXBUF
 #include <gdk-pixbuf/gdk-pixbuf.h>
@@ -971,7 +976,7 @@ static uint32_t *
 parse_mpf_index_entries(const struct tiffer *T, struct tiffer_entry *entry)
 {
 	uint32_t count = entry->remaining_count / 16;
-	uint32_t *offsets = g_malloc0_n(sizeof *offsets, count + 1), *out = offsets;
+	uint32_t *offsets = g_malloc0_n(count + 1, sizeof *offsets), *out = offsets;
 	for (uint32_t i = 0; i < count; i++) {
 		// 5.2.3.3.3. Individual Image Data Offset
 		uint32_t offset = parse_mpf_mpentry(entry->p + i * 16, T);
@@ -1538,9 +1543,11 @@ load_libwebp_frame(WebPAnimDecoder *dec, const WebPAnimInfo *info,
 	if (G_BYTE_ORDER == G_LITTLE_ENDIAN) {
 		memcpy(dst, buf, area * sizeof *dst);
 	} else {
-		uint32_t *src = (uint32_t *) buf;
-		for (uint64_t i = 0; i < area; i++)
-			*dst++ = GUINT32_FROM_LE(*src++);
+		const uint32_t *src = (const uint32_t *) buf;
+		for (uint64_t i = 0; i < area; i++) {
+			uint32_t value = *src++;
+			*dst++ = GUINT32_FROM_LE(value);
+		}
 	}
 
 	// info->bgcolor is not reliable.
@@ -3451,34 +3458,40 @@ fiv_io_orientation_apply(const FivIoImage *image,
 	FivIoOrientation orientation, double *width, double *height)
 {
 	fiv_io_orientation_dimensions(image, orientation, width, height);
+	return fiv_io_orientation_matrix(orientation, *width, *height);
+}
 
+cairo_matrix_t
+fiv_io_orientation_matrix(
+	FivIoOrientation orientation, double width, double height)
+{
 	cairo_matrix_t matrix = {};
 	cairo_matrix_init_identity(&matrix);
 	switch (orientation) {
 	case FivIoOrientation90:
 		cairo_matrix_rotate(&matrix, -M_PI_2);
-		cairo_matrix_translate(&matrix, -*width, 0);
+		cairo_matrix_translate(&matrix, -width, 0);
 		break;
 	case FivIoOrientation180:
 		cairo_matrix_scale(&matrix, -1, -1);
-		cairo_matrix_translate(&matrix, -*width, -*height);
+		cairo_matrix_translate(&matrix, -width, -height);
 		break;
 	case FivIoOrientation270:
 		cairo_matrix_rotate(&matrix, +M_PI_2);
-		cairo_matrix_translate(&matrix, 0, -*height);
+		cairo_matrix_translate(&matrix, 0, -height);
 		break;
 	case FivIoOrientationMirror0:
 		cairo_matrix_scale(&matrix, -1, +1);
-		cairo_matrix_translate(&matrix, -*width, 0);
+		cairo_matrix_translate(&matrix, -width, 0);
 		break;
 	case FivIoOrientationMirror90:
 		cairo_matrix_rotate(&matrix, +M_PI_2);
 		cairo_matrix_scale(&matrix, -1, +1);
-		cairo_matrix_translate(&matrix, -*width, -*height);
+		cairo_matrix_translate(&matrix, -width, -height);
 		break;
 	case FivIoOrientationMirror180:
 		cairo_matrix_scale(&matrix, +1, -1);
-		cairo_matrix_translate(&matrix, 0, -*height);
+		cairo_matrix_translate(&matrix, 0, -height);
 		break;
 	case FivIoOrientationMirror270:
 		cairo_matrix_rotate(&matrix, -M_PI_2);

fiv-io.h

@@ -185,6 +185,8 @@ FivIoImage *fiv_io_open_png_thumbnail(const char *path, GError **error);
 /// and its target dimensions.
 cairo_matrix_t fiv_io_orientation_apply(const FivIoImage *image,
 	FivIoOrientation orientation, double *width, double *height);
+cairo_matrix_t fiv_io_orientation_matrix(
+	FivIoOrientation orientation, double width, double height);
 void fiv_io_orientation_dimensions(const FivIoImage *image,
 	FivIoOrientation orientation, double *width, double *height);
 

fiv-reverse-search

@@ -5,5 +5,5 @@ if [ "$#" -ne 2 ]; then
 fi
 
 xdg-open "$1$(fiv --thumbnail-for-search large "$2" \
-	| curl --silent --show-error --upload-file - https://transfer.sh/image \
-	| jq --slurp --raw-input --raw-output @uri)"
+	| curl --silent --show-error --form 'files[]=@-' https://uguu.se/upload \
+	| jq --raw-output '.files[] | .url | @uri')"

fiv-sidebar.c

@@ -433,7 +433,10 @@ complete_path(GFile *location, GtkListStore *model)
 			!info)
 			break;
 
-		if (g_file_info_get_file_type(info) != G_FILE_TYPE_DIRECTORY ||
+		if (g_file_info_get_file_type(info) != G_FILE_TYPE_DIRECTORY)
+			continue;
+		if (g_file_info_has_attribute(info,
+				G_FILE_ATTRIBUTE_STANDARD_IS_HIDDEN) &&
 			g_file_info_get_is_hidden(info))
 			continue;
 
@@ -534,6 +537,13 @@ on_show_enter_location(
 	g_signal_connect(entry, "changed",
 		G_CALLBACK(on_enter_location_changed), self);
 
+	GFile *location = fiv_io_model_get_location(self->model);
+	if (location) {
+		gchar *parse_name = g_file_get_parse_name(location);
+		gtk_entry_set_text(GTK_ENTRY(entry), parse_name);
+		g_free(parse_name);
+	}
+
 	// Can't have it ellipsized and word-wrapped at the same time.
 	GtkWidget *protocols = gtk_label_new("");
 	gtk_label_set_ellipsize(GTK_LABEL(protocols), PANGO_ELLIPSIZE_END);

fiv-thumbnail.c

@@ -392,7 +392,7 @@ extract_libraw_unpack(libraw_data_t *iprc, int *flip, GError **error)
 	// The main image's "flip" often matches up, but sometimes doesn't, e.g.:
 	//  - Phase One/H 25/H25_Outdoor_.IIQ
 	//  - Phase One/H 25/H25_IT8.7-2_Card.TIF
-	*flip = iprc->sizes.flip
+	*flip = iprc->sizes.flip;
 	return TRUE;
 }
 

fiv-view.c

@@ -1,7 +1,7 @@
 //
 // fiv-view.c: image viewing widget
 //
-// Copyright (c) 2021 - 2022, Přemysl Eric Janouch <p@janouch.name>
+// Copyright (c) 2021 - 2024, Přemysl Eric Janouch <p@janouch.name>
 //
 // Permission to use, copy, modify, and/or distribute this software for any
 // purpose with or without fee is hereby granted.
@@ -24,6 +24,7 @@
 #include <math.h>
 #include <stdbool.h>
 
+#include <epoxy/gl.h>
 #include <gtk/gtk.h>
 #ifdef GDK_WINDOWING_X11
 #include <gdk/gdkx.h>
@@ -83,6 +84,10 @@ struct _FivView {
 	int remaining_loops;                ///< Greater than zero if limited
 	gint64 frame_time;                  ///< Current frame's start, µs precision
 	gulong frame_update_connection;     ///< GdkFrameClock::update
+
+	GdkGLContext *gl_context;           ///< OpenGL context
+	bool gl_initialized;                ///< Objects have been created
+	GLuint gl_program;                  ///< Linked render program
 };
 
 G_DEFINE_TYPE_EXTENDED(FivView, fiv_view, GTK_TYPE_WIDGET, 0,
@@ -161,6 +166,147 @@ enum {
 // Globals are, sadly, the canonical way of storing signal numbers.
 static guint view_signals[LAST_SIGNAL];
 
+// --- OpenGL ------------------------------------------------------------------
+// While GTK+ 3 technically still supports legacy desktop OpenGL 2.0[1],
+// we will pick the 3.3 core profile, which is fairly old by now.
+// It doesn't seem to make any sense to go below 3.2.
+//
+// [1] https://stackoverflow.com/a/37923507/76313
+//
+// OpenGL ES
+//
+// Currently, we do not support OpenGL ES at all--it needs its own shaders
+// (if only because of different #version statements), and also further analysis
+// as to what is our minimum version requirement. While GTK+ 3 can again go
+// down as low as OpenGL ES 2.0, this might be too much of a hassle to support.
+//
+// ES can be forced via GDK_GL=gles, if gdk_gl_context_set_required_version()
+// doesn't stand in the way.
+//
+// Let's not forget that this is a desktop image viewer first and foremost.
+
+static const char *
+gl_error_string(GLenum err)
+{
+	switch (err) {
+	case GL_NO_ERROR:
+		return "no error";
+	case GL_CONTEXT_LOST:
+		return "context lost";
+	case GL_INVALID_ENUM:
+		return "invalid enum";
+	case GL_INVALID_VALUE:
+		return "invalid value";
+	case GL_INVALID_OPERATION:
+		return "invalid operation";
+	case GL_INVALID_FRAMEBUFFER_OPERATION:
+		return "invalid framebuffer operation";
+	case GL_OUT_OF_MEMORY:
+		return "out of memory";
+	case GL_STACK_UNDERFLOW:
+		return "stack underflow";
+	case GL_STACK_OVERFLOW:
+		return "stack overflow";
+	default:
+		return NULL;
+	}
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static const char *gl_vertex =
+	"#version 330\n"
+	"layout(location = 0) in vec4 position;\n"
+	"out vec2 coordinates;\n"
+	"void main() {\n"
+	"\tcoordinates = position.zw;\n"
+	"\tgl_Position = vec4(position.xy, 0., 1.);\n"
+	"}\n";
+
+static const char *gl_fragment =
+	"#version 330\n"
+	"in vec2 coordinates;\n"
+	"layout(location = 0) out vec4 color;\n"
+	"uniform sampler2D picture;\n"
+	"uniform bool checkerboard;\n"
+	"\n"
+	"vec3 checker() {\n"
+	"\tvec2 xy = gl_FragCoord.xy / 20.;\n"
+	"\tif (checkerboard && (int(floor(xy.x) + floor(xy.y)) & 1) == 0)\n"
+	"\t\treturn vec3(0.98);\n"
+	"\telse\n"
+	"\t\treturn vec3(1.00);\n"
+	"}\n"
+	"\n"
+	"void main() {\n"
+	"\tvec3 c = checker();\n"
+	"\tvec4 t = texture(picture, coordinates);\n"
+	"\t// Premultiplied blending with a solid background.\n"
+	"\t// XXX: This is only correct for linear components.\n"
+	"\tcolor = vec4(c * (1. - t.a) + t.rgb, 1.);\n"
+	"}\n";
+
+static GLuint
+gl_make_shader(int type, const char *glsl)
+{
+	GLuint shader = glCreateShader(type);
+	glShaderSource(shader, 1, &glsl, NULL);
+	glCompileShader(shader);
+
+	GLint status = 0;
+	glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
+	if (!status) {
+		GLint len = 0;
+		glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &len);
+
+		GLchar *buffer = g_malloc0(len + 1);
+		glGetShaderInfoLog(shader, len, NULL, buffer);
+		g_warning("GL shader compilation failed: %s", buffer);
+		g_free(buffer);
+
+		glDeleteShader(shader);
+		return 0;
+	}
+	return shader;
+}
+
+static GLuint
+gl_make_program(void)
+{
+	GLuint vertex = gl_make_shader(GL_VERTEX_SHADER, gl_vertex);
+	GLuint fragment = gl_make_shader(GL_FRAGMENT_SHADER, gl_fragment);
+	if (!vertex || !fragment) {
+		glDeleteShader(vertex);
+		glDeleteShader(fragment);
+		return 0;
+	}
+
+	GLuint program = glCreateProgram();
+	glAttachShader(program, vertex);
+	glAttachShader(program, fragment);
+	glLinkProgram(program);
+	glDeleteShader(vertex);
+	glDeleteShader(fragment);
+
+	GLint status = 0;
+	glGetProgramiv(program, GL_LINK_STATUS, &status);
+	if (!status) {
+		GLint len = 0;
+		glGetProgramiv(program, GL_INFO_LOG_LENGTH, &len);
+
+		GLchar *buffer = g_malloc0(len + 1);
+		glGetProgramInfoLog(program, len, NULL, buffer);
+		g_warning("GL program linking failed: %s", buffer);
+		g_free(buffer);
+
+		glDeleteProgram(program);
+		return 0;
+	}
+	return program;
+}
+
+// -----------------------------------------------------------------------------
+
 static void
 on_adjustment_value_changed(
 	G_GNUC_UNUSED GtkAdjustment *adjustment, gpointer user_data)
@@ -500,7 +646,8 @@ reload_screen_cms_profile(FivView *self, GdkWindow *window)
 				gchar *data = NULL;
 				gsize length = 0;
 				if (g_file_get_contents(path, &data, &length, NULL))
-					self->screen_cms_profile = fiv_io_profile_new(data, length);
+					self->screen_cms_profile = fiv_io_cmm_get_profile(
+						fiv_io_cmm_get_default(), data, length);
 				g_free(data);
 			}
 			g_free(path);
@@ -562,6 +709,9 @@ fiv_view_realize(GtkWidget *widget)
 	GdkWindow *window = gdk_window_new(gtk_widget_get_parent_window(widget),
 		&attributes, GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL);
 
+	GSettings *settings = g_settings_new(PROJECT_NS PROJECT_NAME);
+	gboolean opengl = g_settings_get_boolean(settings, "opengl");
+
 	// Without the following call, or the rendering mode set to "recording",
 	// RGB30 degrades to RGB24, because gdk_window_begin_paint_internal()
 	// creates backing stores using cairo_content_t constants.
@@ -571,20 +721,274 @@ fiv_view_realize(GtkWidget *widget)
 	// Note that this disables double buffering, and sometimes causes artefacts,
 	// see: https://gitlab.gnome.org/GNOME/gtk/-/issues/2560
 	//
-	// If GTK+'s OpenGL integration fails to deliver, we need to use the window
-	// directly, sidestepping the toolkit entirely.
-	GSettings *settings = g_settings_new(PROJECT_NS PROJECT_NAME);
+	// GTK+'s OpenGL integration is terrible, so we may need to use
+	// the X11 subwindow directly, sidestepping the toolkit entirely.
 	if (GDK_IS_X11_WINDOW(window) &&
 		g_settings_get_boolean(settings, "native-view-window"))
 		gdk_window_ensure_native(window);
-	g_object_unref(settings);
 #endif  // GDK_WINDOWING_X11
+	g_object_unref(settings);
 
 	gtk_widget_register_window(widget, window);
 	gtk_widget_set_window(widget, window);
 	gtk_widget_set_realized(widget, TRUE);
 
 	reload_screen_cms_profile(FIV_VIEW(widget), window);
+
+	FivView *self = FIV_VIEW(widget);
+	g_clear_object(&self->gl_context);
+	if (!opengl)
+		return;
+
+	GError *error = NULL;
+	GdkGLContext *gl_context = gdk_window_create_gl_context(window, &error);
+	if (!gl_context) {
+		g_warning("GL: %s", error->message);
+		g_error_free(error);
+		return;
+	}
+
+	gdk_gl_context_set_use_es(gl_context, FALSE);
+	gdk_gl_context_set_required_version(gl_context, 3, 3);
+	gdk_gl_context_set_debug_enabled(gl_context, TRUE);
+
+	if (!gdk_gl_context_realize(gl_context, &error)) {
+		g_warning("GL: %s", error->message);
+		g_error_free(error);
+		g_object_unref(gl_context);
+		return;
+	}
+
+	self->gl_context = gl_context;
+}
+
+static void GLAPIENTRY
+gl_on_message(G_GNUC_UNUSED GLenum source, GLenum type, G_GNUC_UNUSED GLuint id,
+	G_GNUC_UNUSED GLenum severity, G_GNUC_UNUSED GLsizei length,
+	const GLchar *message, G_GNUC_UNUSED const void *user_data)
+{
+	if (type == GL_DEBUG_TYPE_ERROR)
+		g_warning("GL: error: %s", message);
+	else
+		g_debug("GL: %s", message);
+}
+
+static void
+fiv_view_unrealize(GtkWidget *widget)
+{
+	FivView *self = FIV_VIEW(widget);
+	if (self->gl_context) {
+		if (self->gl_initialized) {
+			gdk_gl_context_make_current(self->gl_context);
+			glDeleteProgram(self->gl_program);
+		}
+		if (self->gl_context == gdk_gl_context_get_current())
+			gdk_gl_context_clear_current();
+
+		g_clear_object(&self->gl_context);
+	}
+
+	GTK_WIDGET_CLASS(fiv_view_parent_class)->unrealize(widget);
+}
+
+static bool
+gl_draw(FivView *self, cairo_t *cr)
+{
+	gdk_gl_context_make_current(self->gl_context);
+
+	if (!self->gl_initialized) {
+		GLuint program = gl_make_program();
+		if (!program)
+			return false;
+
+		glDisable(GL_SCISSOR_TEST);
+		glDisable(GL_STENCIL_TEST);
+		glDisable(GL_DEPTH_TEST);
+		glDisable(GL_CULL_FACE);
+		glDisable(GL_BLEND);
+		if (epoxy_has_gl_extension("GL_ARB_debug_output")) {
+			glEnable(GL_DEBUG_OUTPUT);
+			glDebugMessageCallback(gl_on_message, NULL);
+		}
+
+		self->gl_program = program;
+		self->gl_initialized = true;
+	}
+
+	// This limit is always less than that of Cairo/pixman,
+	// and we'd have to figure out tiling.
+	GLint max = 0;
+	glGetIntegerv(GL_MAX_TEXTURE_SIZE, &max);
+	if (max < (GLint) self->frame->width ||
+		max < (GLint) self->frame->height) {
+		g_warning("OpenGL max. texture size is too small");
+		return false;
+	}
+
+	GtkAllocation allocation;
+	gtk_widget_get_allocation(GTK_WIDGET(self), &allocation);
+	int dw = 0, dh = 0, dx = 0, dy = 0;
+	get_display_dimensions(self, &dw, &dh);
+
+	int clipw = dw, cliph = dh;
+	double x1 = 0., y1 = 0., x2 = 1., y2 = 1.;
+	if (self->hadjustment)
+		x1 = floor(gtk_adjustment_get_value(self->hadjustment)) / dw;
+	if (self->vadjustment)
+		y1 = floor(gtk_adjustment_get_value(self->vadjustment)) / dh;
+
+	if (dw <= allocation.width) {
+		dx = round((allocation.width - dw) / 2.);
+	} else {
+		x2 = x1 + (double) allocation.width / dw;
+		clipw = allocation.width;
+	}
+
+	if (dh <= allocation.height) {
+		dy = round((allocation.height - dh) / 2.);
+	} else {
+		y2 = y1 + (double) allocation.height / dh;
+		cliph = allocation.height;
+	}
+
+	int scale = gtk_widget_get_scale_factor(GTK_WIDGET(self));
+	clipw *= scale;
+	cliph *= scale;
+
+	enum { SRC, DEST };
+	GLuint textures[2] = {};
+	glGenTextures(2, textures);
+
+	// https://stackoverflow.com/questions/25157306 0..1
+	// GL_TEXTURE_RECTANGLE seems kind-of useful
+	glBindTexture(GL_TEXTURE_2D, textures[SRC]);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	if (self->filter) {
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	} else {
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	}
+
+	// GL_UNPACK_ALIGNMENT is initially 4, which is fine for these.
+	// Texture swizzling is OpenGL 3.3.
+	if (self->frame->format == CAIRO_FORMAT_ARGB32) {
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
+			self->frame->width, self->frame->height,
+			0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, self->frame->data);
+	} else if (self->frame->format == CAIRO_FORMAT_RGB24) {
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_A, GL_ONE);
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
+			self->frame->width, self->frame->height,
+			0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, self->frame->data);
+	} else if (self->frame->format == CAIRO_FORMAT_RGB30) {
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_A, GL_ONE);
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
+			self->frame->width, self->frame->height,
+			0, GL_BGRA, GL_UNSIGNED_INT_2_10_10_10_REV, self->frame->data);
+	} else {
+		g_warning("GL: unsupported bitmap format");
+	}
+
+	// GtkGLArea creates textures like this.
+	glBindTexture(GL_TEXTURE_2D, textures[DEST]);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, clipw, cliph, 0, GL_BGRA,
+		GL_UNSIGNED_BYTE, NULL);
+
+	glViewport(0, 0, clipw, cliph);
+
+	GLuint vao = 0;
+	glGenVertexArrays(1, &vao);
+
+	GLuint frame_buffer = 0;
+	glGenFramebuffers(1, &frame_buffer);
+	glBindFramebuffer(GL_FRAMEBUFFER, frame_buffer);
+	glFramebufferTexture2D(
+		GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[DEST], 0);
+
+	glClearColor(0., 0., 0., 1.);
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+	if (status != GL_FRAMEBUFFER_COMPLETE)
+		g_warning("GL framebuffer status: %u", status);
+
+	glUseProgram(self->gl_program);
+	GLint position_location = glGetAttribLocation(
+		self->gl_program, "position");
+	GLint picture_location = glGetUniformLocation(
+		self->gl_program, "picture");
+	GLint checkerboard_location = glGetUniformLocation(
+		self->gl_program, "checkerboard");
+
+	glUniform1i(picture_location, 0);
+	glUniform1i(checkerboard_location, self->checkerboard);
+	glActiveTexture(GL_TEXTURE0);
+	glBindTexture(GL_TEXTURE_2D, textures[SRC]);
+
+	// Note that the Y axis is flipped in the table.
+	double vertices[][4] = {
+		{-1., -1., x1, y2},
+		{+1., -1., x2, y2},
+		{+1., +1., x2, y1},
+		{-1., +1., x1, y1},
+	};
+
+	cairo_matrix_t matrix = fiv_io_orientation_matrix(self->orientation, 1, 1);
+	cairo_matrix_transform_point(&matrix, &vertices[0][2], &vertices[0][3]);
+	cairo_matrix_transform_point(&matrix, &vertices[1][2], &vertices[1][3]);
+	cairo_matrix_transform_point(&matrix, &vertices[2][2], &vertices[2][3]);
+	cairo_matrix_transform_point(&matrix, &vertices[3][2], &vertices[3][3]);
+
+	GLuint vertex_buffer = 0;
+	glGenBuffers(1, &vertex_buffer);
+	glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer);
+	glBufferData(GL_ARRAY_BUFFER, sizeof vertices, vertices, GL_STATIC_DRAW);
+	glBindVertexArray(vao);
+	glVertexAttribPointer(position_location,
+		G_N_ELEMENTS(vertices[0]), GL_DOUBLE, GL_FALSE, sizeof vertices[0], 0);
+	glEnableVertexAttribArray(position_location);
+	glDrawArrays(GL_TRIANGLE_FAN, 0, G_N_ELEMENTS(vertices));
+	glDisableVertexAttribArray(position_location);
+	glBindVertexArray(0);
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	glUseProgram(0);
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+	// XXX: Native GdkWindows send this to the software fallback path.
+	// XXX: This only reliably alpha blends when using the software fallback,
+	// such as with a native window, because 7237f5d in GTK+ 3 is a regression.
+	// (Introduced in 3.24.39, reverted in 3.24.42.)
+	//
+	// We had to resort to rendering the checkerboard pattern in the shader.
+	// Unfortunately, it is hard to retrieve the theme colours from CSS.
+	GdkWindow *window = gtk_widget_get_window(GTK_WIDGET(self));
+	cairo_translate(cr, dx, dy);
+	gdk_cairo_draw_from_gl(
+		cr, window, textures[DEST], GL_TEXTURE, scale, 0, 0, clipw, cliph);
+	gdk_gl_context_make_current(self->gl_context);
+
+	glDeleteBuffers(1, &vertex_buffer);
+	glDeleteTextures(2, textures);
+	glDeleteVertexArrays(1, &vao);
+	glDeleteFramebuffers(1, &frame_buffer);
+
+	// TODO(p): Possibly use this clue as a hint to use Cairo rendering.
+	GLenum err = 0;
+	while ((err = glGetError()) != GL_NO_ERROR) {
+		const char *string = gl_error_string(err);
+		if (string)
+			g_warning("GL: error: %s", string);
+		else
+			g_warning("GL: error: %u", err);
+	}
+
+	gdk_gl_context_clear_current();
+	return true;
 }
 
 static gboolean
@@ -601,8 +1005,10 @@ fiv_view_draw(GtkWidget *widget, cairo_t *cr)
 	if (!self->image ||
 		!gtk_cairo_should_draw_window(cr, gtk_widget_get_window(widget)))
 		return TRUE;
+	if (self->gl_context && gl_draw(self, cr))
+		return TRUE;
 
-	int dw, dh;
+	int dw = 0, dh = 0;
 	get_display_dimensions(self, &dw, &dh);
 
 	double x = 0;
@@ -1296,6 +1702,7 @@ fiv_view_class_init(FivViewClass *klass)
 	widget_class->map = fiv_view_map;
 	widget_class->unmap = fiv_view_unmap;
 	widget_class->realize = fiv_view_realize;
+	widget_class->unrealize = fiv_view_unrealize;
 	widget_class->draw = fiv_view_draw;
 	widget_class->button_press_event = fiv_view_button_press_event;
 	widget_class->scroll_event = fiv_view_scroll_event;

fiv.gschema.xml

@@ -17,6 +17,13 @@
 				double buffering.
 			</description>
 		</key>
+		<key name='opengl' type='b'>
+			<default>false</default>
+			<summary>Use experimental OpenGL rendering</summary>
+			<description>
+				OpenGL within GTK+ is highly problematic--you don't want this.
+			</description>
+		</key>
 		<key name='dark-theme' type='b'>
 			<default>false</default>
 			<summary>Use a dark theme variant on start-up</summary>

meson.build

@@ -1,7 +1,7 @@
 # vim: noet ts=4 sts=4 sw=4:
 project('fiv', 'c',
 	default_options : ['c_std=gnu99', 'warning_level=2'],
-	version : '0.1.0',
+	version : '1.0.0',
 	meson_version : '>=0.57')
 
 cc = meson.get_compiler('c')
@@ -36,6 +36,7 @@ gdkpixbuf = dependency('gdk-pixbuf-2.0', required : get_option('gdk-pixbuf'))
 dependencies = [
 	dependency('gtk+-3.0'),
 	dependency('pixman-1'),
+	dependency('epoxy'),
 
 	dependency('libjpeg'),
 	dependency('libturbojpeg'),
@@ -165,7 +166,7 @@ tiff_tables = custom_target('tiff-tables.h',
 
 desktops = ['fiv.desktop', 'fiv-browse.desktop']
 iolib = static_library('fiv-io', 'fiv-io.c', 'fiv-io-cmm.c', 'xdg.c',
-	tiff_tables,
+	tiff_tables, config,
 	dependencies : dependencies).extract_all_objects(recursive : true)
 exe = executable('fiv', 'fiv.c', 'fiv-view.c', 'fiv-context-menu.c',
 	'fiv-browser.c', 'fiv-sidebar.c', 'fiv-thumbnail.c', 'fiv-collection.c',
@@ -362,10 +363,12 @@ elif meson.is_cross_build()
 			'ProjectURL' : application_url,
 		}),
 	)
+	msi = meson.project_name() + '-' + meson.project_version() + \
+		'-' + host_machine.cpu() + '.msi'
 	custom_target('package',
-		output : 'fiv.msi',
+		output : msi,
 		command : [meson.current_source_dir() / 'msys2-package.sh',
-			host_machine.cpu(), 'fiv.msi', wxs],
+			host_machine.cpu(), msi, wxs],
 		env : ['MESON_BUILD_ROOT=' + meson.current_build_dir(),
 			'MESON_SOURCE_ROOT=' + meson.current_source_dir()],
 		console : true,

msys2-configure.sh

@@ -75,10 +75,15 @@ extract() {
 		--exclude '*/share/man' --exclude '*/share/doc'
 	done < db.want
 
+	# Don't require Perl, which may not exist anymore on i686:
+	# https://github.com/msys2/MINGW-packages/pull/20085
+	if [ -d lib/perl5 ]
+	then
 		bsdtar -xf exiftool.tar.gz
 		mv Image-ExifTool-*/exiftool bin
 		mv Image-ExifTool-*/lib/* lib/perl5/site_perl
 		rm -rf Image-ExifTool-*
+	fi
 }
 
 configure() {
@@ -125,6 +130,8 @@ setup() {
 		--bindir . --libdir . --cross-file="$toolchain" "$builddir" "$sourcedir"
 }
 
+# Note: you may need GNU coreutils realpath for non-existent build directories
+# (macOS and busybox will probably not work).
 sourcedir=$(realpath "${2:-$(dirname "$0")}")
 builddir=$(realpath "${1:-builddir}")
 toolchain=$builddir/msys2-cross-toolchain.meson

msys2-install.sh

@@ -12,15 +12,15 @@ fi
 
 # Copy binaries we directly or indirectly depend on.
 cp -p "$msys2_root"/bin/*.dll .
-cp -p "$msys2_root"/bin/wperl.exe .
-cp -p "$msys2_root"/bin/exiftool .
+cp -p "$msys2_root"/bin/wperl.exe . || :
+cp -p "$msys2_root"/bin/exiftool . || :
 # The console helper is only useful for debug builds.
 cp -p "$msys2_root"/bin/gspawn-*-helper*.exe .
 cp -pR "$msys2_root"/etc/ .
 
 mkdir -p lib
 cp -pR "$msys2_root"/lib/gdk-pixbuf-2.0/ lib
-cp -pR "$msys2_root"/lib/perl5/ lib
+cp -pR "$msys2_root"/lib/perl5/ lib || :
 mkdir -p share/glib-2.0/schemas
 cp -pR "$msys2_root"/share/glib-2.0/schemas/*.Settings.* share/glib-2.0/schemas
 mkdir -p share/icons

msys2-package.sh

@@ -1,7 +1,8 @@
 #!/bin/sh -e
 export LC_ALL=C
 cd "$MESON_BUILD_ROOT"
-arch=$1 msi=$2 files=package-files.wxs destdir=$(pwd)/package
+arch=$1 msi=$2 files=package-files.wxs
+destdir=$(pwd)/package/${msi%.*}
 shift 2
 
 # We're being passed host_machine.cpu(), which will be either x86 or x86_64.
@@ -15,7 +16,7 @@ txt2rtf() {
 		print "{\\rtf1\\ansi\\ansicpg1252\\deff0{\\fonttbl{\\f0 Tahoma;}}"
 		print "\\f0\\fs24{\\pard\\sa240"
 	} {
-		gsub(/\\/, "\\\\"); gsub(/{/, "\\{"); gsub(/}/, "\\}")
+		gsub(/\\/, "\\\\"); gsub(/[{]/, "\\{"); gsub(/[}]/, "\\}")
 		if (!$0) { print "\\par}{\\pard\\sa240"; prefix = "" }
 		else { print prefix $0; prefix = " " }
 	} END {