Create some uses of buffer to create_graphics

Author: monkstone

examples/buffer/buffer.rb

@@ -0,0 +1,27 @@
+# Using the JRubyArt convenience method buffer to create_graphics you
+# do not need to begin_draw, end_draw since the buffer method wraps them
+# around user provided block. In practice you probably won't use this method
+# much, because you should avoid creating offscreen buffers in the draw loop.
+# This sketch is OK because you create the offscreen graphics in the setup.
+
+attr_reader :pg
+
+def setup
+  sketch_title 'Create graphics using :buffer'
+  @pg = buffer(60, 70, P2D) do |buf|
+    buf.background 51
+    buf.no_fill
+    buf.stroke 255
+    buf.rect 0, 0, 59, 69
+  end
+end
+
+def draw
+  fill 0, 12
+  rect 0, 0, width, height
+  image pg, mouse_x - 60, mouse_y - 70
+end
+
+def settings
+  size 640, 380, P2D
+end

examples/grid_method/luciernagas.rb

@@ -52,16 +52,15 @@ def draw
 end
 
 def draw_lights
-  lights = create_graphics width, height, P2D
-  lights.begin_draw
-  @flyers.each do |flyer|
-    lights.push_matrix
-    position = flyer.pos
-    lights.translate position.x, position.y
-    lights.image @spotlight, -@spotlight.width / 2, -@spotlight.height / 2
-    lights.pop_matrix
+  lights = buffer(width, height, P2D) do |buffer|
+    @flyers.each do |flyer|
+      buffer.push_matrix
+      position = flyer.pos
+      buffer.translate position.x, position.y
+      buffer.image @spotlight, -@spotlight.width / 2, -@spotlight.height / 2
+      buffer.pop_matrix
+    end
   end
-  lights.end_draw
   image_mask.mask lights
   image image_mask, 0, 0
 end
@@ -152,14 +151,12 @@ def find_nearest_rotation(from, to)
 
 def create_spotlight
   size = 60
-  spotlight = create_graphics size, size, P2D
-  spotlight.begin_draw
-  spotlight.no_stroke
-  spotlight.fill 255, 60
-  # spotlight.fill 255, 40
   half_size = size / 2
-  spotlight.ellipse half_size, half_size, half_size, half_size
-  spotlight.filter BLUR, 4
-  spotlight.end_draw
-  spotlight
+  spotlight = buffer(size, size, P2D) do |buffer|
+    buffer.no_stroke
+    buffer.fill 255, 60
+    # spotlight.fill 255, 40    
+    buffer.ellipse half_size, half_size, half_size, half_size
+    buffer.filter BLUR, 4
+  end
 end

processing_app/basics/structure/create_graphics.rb

@@ -1,29 +1,30 @@
-# Create Graphics. 
-# 
-# The createGraphics() function creates an object from the PGraphics class 
-# (PGraphics is the main graphics and rendering context for Processing). 
+# Create Graphics.
+#
+# The createGraphics() function creates an object from the PGraphics class
+# (PGraphics is the main graphics and rendering context for Processing).
 # The beginDraw() method is necessary to prepare for drawing and endDraw() is
-# necessary to finish. Use this class if you need to draw into an off-screen 
+# necessary to finish. Use this class if you need to draw into an off-screen
 # graphics buffer or to maintain two contexts with different properties.
+attr_reader :pg
 
 def setup
   sketch_title 'Create Graphics'
   @pg = create_graphics 400, 200
 end
 
-def draw  
+def draw
   fill 0, 12
-  rect 0, 0, width, height  	
+  rect 0, 0, width, height
   fill 255
   no_stroke
-  ellipse mouse_x, mouse_y, 60, 60  	
-  @pg.begin_draw
-  @pg.background 51
-  @pg.no_fill
-  @pg.stroke 255
-  @pg.ellipse mouse_x-60, mouse_y-60, 60, 60
-  @pg.end_draw  	
-  image @pg, 120, 60
+  ellipse mouse_x, mouse_y, 60, 60
+  pg.begin_draw
+  pg.background 51
+  pg.no_fill
+  pg.stroke 255
+  pg.ellipse mouse_x - 60, mouse_y - 60, 60, 60
+  pg.end_draw
+  image pg, 120, 60
 end
 
 def settings

processing_app/demos/graphics/trefoil.rb

@@ -13,12 +13,11 @@ def setup
   texture_mode(NORMAL)
   no_stroke
   # Creating offscreen surface for 3D rendering.
-  @pg = create_graphics(32, 512, P3D)
-  pg.begin_draw
-  pg.background(0, 0)
-  pg.noStroke
-  pg.fill(255, 0, 0, 200)
-  pg.end_draw
+  @pg = buffer(32, 512, P3D) do |buf|
+    buf.background(0, 0)
+    buf.no_stroke
+    buf.fill(255, 0, 0, 200)
+  end
   # Saving trefoil surface into a PShape3D object
   @trefoil = create_trefoil(350, 60, 15, pg)
 end
@@ -29,7 +28,7 @@ def draw
   pg.ellipse(rand(0.0..pg.width), rand(0.0..pg.height), 4, 4)
   pg.end_draw
   ambient(250, 250, 250)
-  pointLight(255, 255, 255, 0, 0, 200)
+  point_light(255, 255, 255, 0, 0, 200)
   push_matrix
   translate(width / 2, height / 2, -200)
   rotate_x(frame_count * PI / 500)

processing_app/topics/drawing/pulses.rb

@@ -1,6 +1,6 @@
 #
-# Pulses. 
-# 
+# Pulses.
+#
 # Software drawing instruments can follow a rhythm or abide by rules independent
 # of drawn gestures. This is a form of collaborative drawing in which the draftsperson
 # controls some aspects of the image and the software controls others.
@@ -20,8 +20,8 @@ def draw
   # Draw only when mouse is pressed
   if mouse_pressed?
     @angle += 5
-    val = cos(angle.radians) * 12.0
-    (0 ... 360).step(75) do |a|
+    val = DegLut.cos(angle) * 12.0
+    (0...360).step(75) do |a|
       xoff = cos(a.radians) * val
       yoff = sin(a.radians) * val
       fill(0)
@@ -35,4 +35,3 @@ def draw
 def settings
   size(640, 360)
 end
-

processing_app/topics/shaders/blur_filter.rb

@@ -1,30 +1,27 @@
 #
 # Blur Filter
-# 
+#
 # Change the default shader to apply a simple, custom blur filter.
-# 
+#
 # Press the mouse to switch between the custom and default shader.
 #
 
 attr_reader :blur
 
 def setup
   sketch_title 'Blur filter'
-  @blur = load_shader(data_path('blur.glsl')) 
-  # @blur = load_shader('blur.glsl') 
+  @blur = load_shader(data_path('blur.glsl'))
+  # @blur = load_shader('blur.glsl')
   stroke(255, 0, 0)
   rectMode(CENTER)
 end
 
 def draw
-  filter(blur)  
-  rect(mouse_x, mouse_y, 150, 150) 
+  filter(blur)
+  rect(mouse_x, mouse_y, 150, 150)
   ellipse(mouse_x, mouse_y, 100, 100)
 end
 
-
-
-
 def settings
   size(640, 360, P2D)
 end