Refactored image.py and load_pixels (#383)

* Refactored image.py to support image apis for different rendering backends.
load_pixels is no longer a context manager as it was different than p5.js and update_pixel is implemented

* Make PImage an abstract class

* Use renderer specific PImage in each renderer

* Update docs

* Format using black

* Use self instead of instance.

docs/examples/image/alpha mask.rst

@@ -52,7 +52,7 @@ Loads a "mask" for an image to specify the transparency in different parts of th
 	def draw():
 	    global img
 	    background(0, 102, 153)
-	    image(img, (width / 2, height / 2))
+	    image(img, width / 2, height / 2)
 	    image(img, mouse_x, mouse_y)
 
 	if __name__ == '__main__':

docs/examples/image/load and display image.rst

@@ -40,8 +40,8 @@ Images can be loaded and displayed to the screen at their actual size or any oth
     def draw():
         global img
         background(0)
-        image(img, (0, 0))
-        image(img, (0, height / 2), (img.width / 2, img.height / 2))
+        image(img, 0, 0)
+        image(img, 0, height / 2, img.width / 2, img.height / 2)
 
     if __name__ == '__main__':
         run()

docs/examples/image/transparency.rst

@@ -45,12 +45,12 @@ Move the pointer left and right across the image to change its position. This pr
 	def draw():
 		global img, offset, easing
 
-		image(img, (0, 0)) #Display at full opacity
+		image(img, 0, 0) #Display at full opacity
 
 		dx = mouse_x - img.width / 2 - offset
 		offset += dx * easing
 		tint(255, 127)
-		image(img, (offset, 0))
+		image(img, offset, 0)
 
 	if __name__ == '__main__':
 		run()

docs/tutorials/data.rst

@@ -576,7 +576,7 @@ The following code retrieves both the running time and movie poster iamge from I
 		global poster, runningtime
 		# Display all the stuff I want to display
 		background(255)
-		image(poster, (10, 10), 164, 250)
+		image(poster, 10, 10, 164, 250)
 		fill(0)
 		text("Shaun the Sheep", (10, 300))
 		text(runningtime, (10, 320))

docs/tutorials/images and pixels.rst

@@ -35,7 +35,7 @@ In addition to user-defined objects (such as Ball), Processing has a bunch of ha
 	def draw():
 		background(0)
 		# Draw the image to the screen at coordinate (0,0)
-		image(img, (0, 0))
+		image(img, 0, 0)
 
 	if __name__ == '__main__':
 		run()
@@ -64,7 +64,7 @@ Once the image is loaded, it is displayed with the ``image()`` function. The ``i
 
 .. code:: python
 
-	image(img, (10,20), (90,60))
+	image(img, 10,20, 90,60)
 
 Your very first image processing filter
 =======================================
@@ -88,7 +88,7 @@ If ``tint()`` receives one argument, only the brightness of the image is affecte
 
 	# The image retains its original state.
 	tint(255)
-	image(sunflower, (0, 0))
+	image(sunflower, 0, 0)
 
 .. image:: ./images_and_pixels-res/tint2.jpg
    :align: left
@@ -97,7 +97,7 @@ If ``tint()`` receives one argument, only the brightness of the image is affecte
 
 	# The image appears darker
 	tint(100)
-	image(sunflower, (0, 0))
+	image(sunflower, 0, 0)
 
 A second argument will change the image's alpha transparency.
 
@@ -108,7 +108,7 @@ A second argument will change the image's alpha transparency.
 
 	# The image is at 50% opacity.
 	tint(100, 127)
-	image(sunflower, (0, 0))
+	image(sunflower, 0, 0)
 
 Three arguments affect the brightness of the red, green, and blue components of each color.
 
@@ -119,7 +119,7 @@ Three arguments affect the brightness of the red, green, and blue components of
 
 	# None of its red, most of its green, and all of its blue.
 	tint(0, 200, 255)
-	image(sunflower, (0, 0))
+	image(sunflower, 0, 0)
 
 Finally, adding a fourth argument to the method manipulates the alpha (same as with 2). Incidentally, the range of values for tint() can be specified with colorMode().
 
@@ -130,7 +130,7 @@ Finally, adding a fourth argument to the method manipulates the alpha (same as w
 
 	# The image is tinted red and transparent.
 	tint(255, 0, 0, 100)
-	image(sunflower, (0, 0))
+	image(sunflower, 0, 0)
 
 Pixels, pixels, and more pixels
 ===============================