From 345479e7ba40ceef04065c4604cd4e651e53741a Mon Sep 17 00:00:00 2001 From: Manuel Kaufmann Date: Tue, 23 Oct 2012 13:41:05 +0000 Subject: Rotate, Zoom and center the image Improves the rotation by centering the image on the screen when it is smaller than the screen size. Optimal zoom is calculated for images than are higher in hight when they are rotated as well. Fixed rotation (anti)clockwise. X, Y axis + angles in gradians are handled different by cairo. Signed-off-by: Manuel Kaufmann Signed-off-by: Agustin Zubiaga --- diff --git a/ImageView.py b/ImageView.py index 30b19ac..cbc5516 100644 --- a/ImageView.py +++ b/ImageView.py @@ -27,6 +27,7 @@ import logging import cairo import random import time +import math ZOOM_IN_OUT = 0.1 @@ -71,6 +72,7 @@ class ImageViewer(Gtk.DrawingArea): self._fast = True self._redraw_id = None self._is_touching = False + self._switched = False def do_get_property(self, pspec): if pspec.name == 'zoom': @@ -123,35 +125,64 @@ class ImageViewer(Gtk.DrawingArea): h = int(self.surface.get_height() * self.zoom) logging.error('W: %s, H: %s', w, h) - ctx.save() if self._fast: ctx.set_antialias(cairo.ANTIALIAS_NONE) - if self.angle != 0: - logging.error('Rotating: %s', self.angle) - ctx.translate(0.5 * w, 0.5 * h) - ctx.rotate(self.angle) - ctx.translate(-0.5 * w, -0.5 * h) scrolled_window = self.get_parent() rect = scrolled_window.get_allocation() x = y = 0 - if rect.width >= w: - x = int((rect.width - w) / 2) - elif self._is_touching: - hadj = int((w - rect.width) / 2) - hadjustment = scrolled_window.get_hadjustment() - hadjustment.set_value(hadj) - - if rect.height >= h: - y = int((rect.height - h) / 2) - elif self._is_touching: - vadj = int((h - rect.height) / 2) - vadjustment = scrolled_window.get_vadjustment() - vadjustment.set_value(vadj) + if self.angle != 0: + logging.error('Rotating: %s', self.angle) + ctx.rotate(self.angle) + + if self.angle == math.pi: + ctx.translate(-w, -h) + + if rect.width > w: + x = -(rect.width - w) / 2 + if rect.height > h: + y = -(rect.height - h) / 2 + + elif self.angle == math.pi / 2: + ctx.translate(0, -h) + + # center the image + if rect.height > w: + x = (rect.height - w) / 2 + if rect.width > h: + y = -(rect.width - h) / 2 + + elif self.angle == math.pi * 3 / 2: + ctx.translate(-w, 0) + + if rect.height > w: + x = -(rect.height - w) / 2 + if rect.width > h: + y = (rect.width - h) / 2 + + else: + if rect.width > w: + x = int((rect.width - w) / 2) + if rect.height > h: + y = int((rect.height - h) / 2) + ctx.translate(x, y) + + if self._is_touching: + if self._switched: + w, h = h, w + + if rect.height < h: + vadj = int((h - rect.height) / 2) + vadjustment = scrolled_window.get_vadjustment() + vadjustment.set_value(vadj) + + if rect.width < w: + hadj = int((w - rect.width) / 2) + hadjustment = scrolled_window.get_hadjustment() + hadjustment.set_value(hadj) if self.zoom != 1: logging.error('Scaling: %s', self.zoom) - ctx.translate(x, y) ctx.scale(self.zoom, self.zoom) ctx.set_source_surface(self.surface, 0, 0) @@ -171,9 +202,23 @@ class ImageViewer(Gtk.DrawingArea): def _redraw_high_quality(self): self._fast = False self._redraw_id = None - self.queue_draw() + self._redraw() return False + def _redraw(self): + # README: this is a hack to not raise the 'draw' event (again) + # when we request more space to show the scroll bars + w = int(self.surface.get_width() * self.zoom) + h = int(self.surface.get_height() * self.zoom) + + self._switched = False + if (self.angle / (math.pi / 2)) % 2 == 1: + # change image dimensions if it's rotated + w, h = h, w + self._switched = True + + self.set_size_request(w, h) + def set_zoom(self, zoom): self._optimal_zoom_flag = False self._set_zoom(zoom) @@ -191,8 +236,8 @@ class ImageViewer(Gtk.DrawingArea): def set_angle(self, angle): self._optimal_zoom_flag = True - self.angle = angle - self.queue_draw() + self.angle = angle % (2 * math.pi) + self._redraw() self.emit('angle-changed') def zoom_in(self): @@ -238,11 +283,18 @@ class ImageViewer(Gtk.DrawingArea): width = rect.width height = rect.height - if width < self.surface.get_width() or \ - height < self.surface.get_height(): + surface_width = self.surface.get_width() + surface_height = self.surface.get_height() + + if self._switched: + surface_width, surface_height = \ + surface_height, surface_width + + if width < surface_width or \ + height < surface_height: # Image is larger than allocated size - zoom = min(width / self.surface.get_width(), - height / self.surface.get_height()) + zoom = min(width / surface_width, + height / surface_height) else: zoom = 1 @@ -251,12 +303,7 @@ class ImageViewer(Gtk.DrawingArea): def _set_zoom(self, zoom): self.zoom = zoom -# # README: this is a hack to not raise the 'draw' event (again) -# # when we request more space to show the scroll bars - self._fast = True - w = int(self.surface.get_width() * self.zoom) - h = int(self.surface.get_height() * self.zoom) - self.set_size_request(w, h) + self._redraw() self.emit('zoom-changed') diff --git a/ImageViewerActivity.py b/ImageViewerActivity.py index f17d4cf..3b36103 100644 --- a/ImageViewerActivity.py +++ b/ImageViewerActivity.py @@ -310,11 +310,11 @@ class ImageViewerActivity(activity.Activity): self.view.set_zoom(1) def __rotate_anticlockwise_cb(self, button): - angle = self.view.angle + math.pi / 2 + angle = self.view.angle - math.pi / 2 self.view.set_angle(angle) def __rotate_clockwise_cb(self, button): - angle = self.view.angle - math.pi / 2 + angle = self.view.angle + math.pi / 2 self.view.set_angle(angle) def __fullscreen_cb(self, button): -- cgit v0.9.1