Diagram.py: don't draw the dot at 0,0 when drawing rectangles

[experiments/RadialSymmetry.git] / Diagram.py

diff --git a/Diagram.py b/Diagram.py
index 0bc3925..1e9b172 100755 (executable)
--- a/Diagram.py
+++ b/Diagram.py
@@ -23,7 +23,7 @@ from math import *
 
 class Diagram(object):
 
 
 class Diagram(object):
 

-    def __init__(self, width, height, background=[1, 1, 1]):
+    def __init__(self, width, height, background=[1, 1, 1], font_size=20):

         self.width = width
         self.height = height
         self.background = background
         self.width = width
         self.height = height
         self.background = background


@@ -38,7 +38,7 @@ class Diagram(object):
 
         cr.select_font_face("Georgia", cairo.FONT_SLANT_NORMAL,
                             cairo.FONT_WEIGHT_NORMAL)
 
         cr.select_font_face("Georgia", cairo.FONT_SLANT_NORMAL,
                             cairo.FONT_WEIGHT_NORMAL)

-        cr.set_font_size(20)
+        cr.set_font_size(font_size)

 
         # Adjust the font matrix to left-bottom origin
         M = cr.get_font_matrix()
 
         # Adjust the font matrix to left-bottom origin
         M = cr.get_font_matrix()


@@ -97,39 +97,36 @@ class Diagram(object):
         else:
             return None
 
         else:
             return None
 

-    def draw_polygon(self, verts, stroke_color=[0, 0, 0], fill_color=None):
+    def _draw_polygon(self, verts):

         cr = self.cr
 
         cr = self.cr
 

-        if fill_color:
-            v = verts[0]
-            cr.move_to(v[0], v[1])
-            for v in verts[1:]:
-                cr.line_to(v[0], v[1])
-                cr.close_path()
+        v = verts[0]
+        cr.move_to(v[0], v[1])
+        for v in verts[1:]:
+            cr.line_to(v[0], v[1])
+        cr.close_path()
+
+    def draw_polygon(self, verts, fill_color=None, stroke_color=[0, 0, 0]):
+        cr = self.cr

 
 

+        if fill_color:
+            self._draw_polygon(verts)

             r, g, b, a = self.color_to_rgba(fill_color)
             cr.set_source_rgba(r, g, b, a)
             cr.fill()
 
             r, g, b, a = self.color_to_rgba(fill_color)
             cr.set_source_rgba(r, g, b, a)
             cr.fill()
 

-        n = len(verts)
-        for i in range(0, n):
-            v1 = verts[i]
-            v2 = verts[(i + 1) % n]
-            cr.move_to(v1[0], v1[1])
-            cr.line_to(v2[0], v2[1])
-
-        r, g, b, a = self.color_to_rgba(stroke_color)
-        cr.set_source_rgba(r, g, b, a)
-        cr.stroke()
+        if stroke_color:
+            self._draw_polygon(verts)
+            r, g, b, a = self.color_to_rgba(stroke_color)
+            cr.set_source_rgba(r, g, b, a)
+            cr.stroke()

 
     def draw_star(self, cx, cy, verts, stroke_color=[0, 0, 0]):
         cr = self.cr
 
 
     def draw_star(self, cx, cy, verts, stroke_color=[0, 0, 0]):
         cr = self.cr
 

-        v = verts[0]
-        cr.move_to(cx, cy)

         for v in verts:
         for v in verts:

-            cr.line_to(v[0], v[1])

             cr.move_to(cx, cy)
             cr.move_to(cx, cy)

+            cr.line_to(v[0], v[1])

 
         r, g, b, a = self.color_to_rgba(stroke_color)
         cr.set_source_rgba(r, g, b, a)
 
         r, g, b, a = self.color_to_rgba(stroke_color)
         cr.set_source_rgba(r, g, b, a)


@@ -139,8 +136,8 @@ class Diagram(object):
         cr = self.cr
 
         cr.save()
         cr = self.cr
 
         cr.save()

-        cr.set_source_rgba(fill_color[0], fill_color[1], fill_color[2],
-                           fill_color[3])
+        r, g, b, a = self.color_to_rgba(fill_color)
+        cr.set_source_rgba(r, g, b, a)

         cr.arc(cx, cy, size, 0, 2 * pi)
         cr.fill()
         cr.restore()
         cr.arc(cx, cy, size, 0, 2 * pi)
         cr.fill()
         cr.restore()


@@ -157,63 +154,66 @@ class Diagram(object):
         cr.stroke()
 
     def draw_rect_from_center(self, cx, cy, width, height, theta=0,
         cr.stroke()
 
     def draw_rect_from_center(self, cx, cy, width, height, theta=0,

-                              fill=True, fill_color=[1, 1, 1],
-                              stroke=False, stroke_color=[0, 0, 0]):
+                              fill=True, fill_color=[1, 1, 1, 0.8],
+                              stroke=False, stroke_color=[0, 0, 0, 0.5]):

         cr = self.cr
 
         cr = self.cr
 

+        # the position of the center of a rectangle at (0,0)

         mx = width / 2.0
         my = height / 2.0
 
         mx = width / 2.0
         my = height / 2.0
 

+        # calculate the position of the bottom-left corner after rotating the
+        # rectangle around the center

         rx = cx - (mx * cos(theta) - my * sin(theta))
         ry = cy - (mx * sin(theta) + my * cos(theta))
 
         rx = cx - (mx * cos(theta) - my * sin(theta))
         ry = cy - (mx * sin(theta) + my * cos(theta))
 

-        cr.save()
-        cr.translate(rx, ry)
-        cr.rotate(theta)
-
-        if fill:
-            cr.rectangle(0, 0, width, height)
-            cr.set_source_rgba(fill_color[0], fill_color[1], fill_color[2], 0.8)
-            cr.fill()
-
-        if stroke:
-            cr.rectangle(0, 0, width, height)
-            cr.set_source_rgba(stroke_color[0], stroke_color[1], stroke_color[2], 0.5)
-            cr.stroke()
-            self.draw_dot(0, 0, 3.0, list(stroke_color) + [0.5])
+        self.draw_rect(rx, ry, width, height, theta, fill, fill_color, stroke,
+                       stroke_color)

 
 

-        cr.restore()
-
-    def draw_rect(self, x, y, width, height, fill=True, fill_color=[1, 1, 1],
-                  stroke=False, stroke_color=[0, 0, 0]):
+    def draw_rect(self, x, y, width, height, theta=0, fill=True, fill_color=[1, 1, 1, 0.8],
+                  stroke=False, stroke_color=[0, 0, 0, 0.5]):

         cr = self.cr
 
         cr.save()
         cr.translate(x, y)
         cr = self.cr
 
         cr.save()
         cr.translate(x, y)

+        cr.rotate(theta)

 
         if fill:
             cr.rectangle(0, 0, width, height)
 
         if fill:
             cr.rectangle(0, 0, width, height)

-            cr.set_source_rgba(fill_color[0], fill_color[1], fill_color[2], 0.8)
+            r, g, b, a = self.color_to_rgba(fill_color)
+            cr.set_source_rgba(r, g, b, a)

             cr.fill()
 
         if stroke:
             cr.rectangle(0, 0, width, height)
             cr.fill()
 
         if stroke:
             cr.rectangle(0, 0, width, height)

-            cr.set_source_rgba(stroke_color[0], stroke_color[1], stroke_color[2], 0.5)
+            r, g, b, a = self.color_to_rgba(stroke_color)
+            cr.set_source_rgba(r, g, b, a)

             cr.stroke()
             cr.stroke()

-            self.draw_dot(0, 0, 3.0, list(stroke_color) + [0.5])

 
         cr.restore()
 
 
         cr.restore()
 

-    def draw_centered_text(self, cx, cy, text, theta=0, color=[0, 0, 0], bounding_box=False):
+    def draw_centered_text(self, cx, cy, text, theta=0,
+                           color=[0, 0, 0],
+                           align_baseline=False,
+                           bb_fill=True, bb_fill_color=[1, 1, 1, 0.8],
+                           bb_stroke=False, bb_stroke_color=[0, 0, 0, 0.5]):

         cr = self.cr
 
         x_bearing, y_bearing, width, height, x_advance = cr.text_extents(text)[:5]
         ascent, descent = cr.font_extents()[:2]
 
         # The offset of the lower-left corner of the text.
         cr = self.cr
 
         x_bearing, y_bearing, width, height, x_advance = cr.text_extents(text)[:5]
         ascent, descent = cr.font_extents()[:2]
 
         # The offset of the lower-left corner of the text.

-        # NOTE: y is kept on the baseline

         tx = width / 2.0 + x_bearing
         tx = width / 2.0 + x_bearing

-        ty = 0
+
+        if align_baseline:
+            # When aligning to the  baseline it is convenient the make the
+            # bounding box depend on the font vertical extent and not from the
+            # text content.
+            ty = 0
+            bb = [0, -descent, width, ascent]
+        else:
+            ty = height / 2.0 + y_bearing
+            bb = [0, y_bearing, width, height]

 
         # Angles are intended clockwise by the caller, but the trigonometric
         # functions below consider angles counter-clockwise
 
         # Angles are intended clockwise by the caller, but the trigonometric
         # functions below consider angles counter-clockwise


@@ -226,8 +226,12 @@ class Diagram(object):
         cr.save()
         cr.translate(rx, ry)
         cr.rotate(theta)
         cr.save()
         cr.translate(rx, ry)
         cr.rotate(theta)

-        self.draw_rect(0, -descent, width, ascent, fill_color=[1, 1, 1, 0.1], stroke=bounding_box)
-        cr.set_source_rgba(color[0], color[1], color[2], 0.8)
+
+        if bb_fill or bb_stroke:
+            self.draw_rect(bb[0], bb[1], bb[2], bb[3], 0, bb_fill, bb_fill_color, bb_stroke, bb_stroke_color)
+
+        r, g, b, a = self.color_to_rgba(color)
+        cr.set_source_rgba(r, g, b, a)

         cr.move_to(0, 0)
         cr.show_text(text)
         cr.fill()
         cr.move_to(0, 0)
         cr.show_text(text)
         cr.fill()


@@ -248,30 +252,36 @@ if __name__ == "__main__":
 
     theta = 0
 
 
     theta = 0
 

-    advance = diagram.draw_centered_text(x_offset, y, "Ciao", theta, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "Ciao", theta, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "____", theta + pi / 4, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "____", theta + pi / 4, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "jxpqdlf", theta + pi / 2, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "jxpqdlf", theta + pi / 2, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "pppp", theta + 3 * pi / 4, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "pppp", theta + 3 * pi / 4, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "dddd", theta + pi, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "dddd", theta + pi, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "Jjjj", theta + 5 * pi / 4, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "Jjjj", theta + 5 * pi / 4, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "1369", theta + 3 * pi / 2, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "1369", theta + 3 * pi / 2, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     x_offset += advance
 

-    advance = diagram.draw_centered_text(x_offset, y, "qqqq", theta + 7 * pi / 4, bounding_box=True)
+    advance = diagram.draw_centered_text(x_offset, y, "qqqq", theta + 7 * pi / 4, align_baseline=True, bb_stroke=True)

     x_offset += advance
 
     diagram.draw_line(0, y, 400, y, [0, 0, 1, 0.2])
 
     x_offset += advance
 
     diagram.draw_line(0, y, 400, y, [0, 0, 1, 0.2])
 

+    diagram.draw_rect(40, 40, 300, 100, stroke=True)
+    diagram.draw_rect(40, 40, 300, 100, pi / 30, stroke=True)
+
+    diagram.draw_rect(40, 250, 300, 100, stroke=True)
+    diagram.draw_rect_from_center(40 + 150, 250 + 50, 300, 100, theta=pi / 40, stroke=True, stroke_color=[1, 0, 0], fill=False)
+

     diagram.show()
     diagram.show()