I'm trying to draw a straight thick line. To do that the easiest way is to use some code that look like this:
However for my current project it comes with 2 problems. The first actually just a disadvantage, it's very ineffecient and slow. The second problem I have is that most pixels are actually drawn multiple times.
Example:
I'm trying to draw some rocks on the floor in a straight thick line, however it should only be drawn 50% of the time, so that not the whole floor is filled with rocks. While drawing this, the following will happen if a pixel is drawn more than once:
First time the chance will be 50%
Second time the chance will be 50% it has been drawn the first time, and again 50% it will be drawn this time. (= 75%)
Third time it will be 87,5%
I hope you understand why I want pixels only to be drawn once. The following Algorithm explains how to draw a thick line:
http://homepages.enterprise.net/murphy/ ... index.html
It uses the Bresenham's line algorithm. It draws multiple parralel lines, in a way that it looks like one thick line. The website provides some explanation, notes and a example code in Pascal.
Sadly I don't understand Pascal at all. Not only that he uses variable names like u, v, p, and q which doesn't help me at all.
I'm able to draw single straight lines, but it's impossible for me to draw thicklines. If anyone would be able to help I would be really happy. I included some code that I use to test my drawing function. If a pixel is drawn, it will turn green, if it's drawn twice or more, it will turn red.
Code:
def drawLine(x1, y1, x2, y2, width = 1)
# Reverse all parameters sent if 2 x is less than the first x
x1, x2, y1, y2 = x2, x1, y2, y1 if x2 < x1
# Get S (1/2 width)
s = width / 2.0
# If X Coordinates are equal
if x1 == x2
# Draw Vertical line
drawSquare(x1 - s, [y1, y2].min, width, (y2 - y1).abs)
# If Y Coordinates are equal
elsif y1 == y2
# Draw Horizontal line
drawSquare(x1, y1 - s, x2 - x1, width)
end
# Get Length
length = x2 - x1 < (y2 - y1).abs ? (y2 - y1).abs : x2 - x1
# Get Increments
x_increment, y_increment = (x2 - x1) / length.to_f, (y2 - y1) / length.to_f
# Get Current X and Y
x, y = x1, y1
# While Current X is less than end X
while x < x2
# Draw Box of width width and width height
drawSquare(x-s, y-s, width, width)
# Increment X and Y
x += x_increment
y += y_increment
end
endHowever for my current project it comes with 2 problems. The first actually just a disadvantage, it's very ineffecient and slow. The second problem I have is that most pixels are actually drawn multiple times.
Example:
I'm trying to draw some rocks on the floor in a straight thick line, however it should only be drawn 50% of the time, so that not the whole floor is filled with rocks. While drawing this, the following will happen if a pixel is drawn more than once:
First time the chance will be 50%
Second time the chance will be 50% it has been drawn the first time, and again 50% it will be drawn this time. (= 75%)
Third time it will be 87,5%
I hope you understand why I want pixels only to be drawn once. The following Algorithm explains how to draw a thick line:
http://homepages.enterprise.net/murphy/ ... index.html
It uses the Bresenham's line algorithm. It draws multiple parralel lines, in a way that it looks like one thick line. The website provides some explanation, notes and a example code in Pascal.
Sadly I don't understand Pascal at all. Not only that he uses variable names like u, v, p, and q which doesn't help me at all.
I'm able to draw single straight lines, but it's impossible for me to draw thicklines. If anyone would be able to help I would be really happy. I included some code that I use to test my drawing function. If a pixel is drawn, it will turn green, if it's drawn twice or more, it will turn red.
Code:
class Bitmap
def draw(x, y)
if get_pixel(x, y) == Color.new(0, 255, 0)
set_pixel(x, y, Color.new(255, 0, 0))
else
set_pixel(x, y, Color.new(0, 255, 0))
end
end
def fill
for x in 0...self.width
for y in 0...self.height
draw(x, y)
end
end
end
def drawSingleLine(x1, y1, x2, y2, f = 0)
dx = x2 - x1
dy = y2 - y1
if dx >= 0
stepx = 1
else
stepx = -1
dx = dx.abs
end
if dy >= 0
stepy = 1
else
stepy = -1
dy = dy.abs
end
dx *= 2
dy *= 2
draw(x1, y1)
if dx >= dy
fraction = 2 * dy - dx
while x1 != x2
if fraction >= 0
y1 += stepy
fraction -= dx
end
x1 += stepx
fraction += dy
draw(x1, y1)
end
else
fraction = 2 * dx - dy
while y1 != y2
if fraction >= 0
x1 += stepx
fraction -= dy
end
y1 += stepy
fraction += dx
draw(x1, y1)
end
end
end
def drawLine(x1, y1, x2, y2, width)
dx = x2 - x1
dy = y2 - y1
drawSingleLine(x1, y1, x2, y2)
end
end
#==============================================================================
# ** Scene_Paint
#------------------------------------------------------------------------------
# This class performs title screen processing.
#==============================================================================
class Scene_Paint
#--------------------------------------------------------------------------
# * Main Processing
#--------------------------------------------------------------------------
def main
# If battle test
if $BTEST
battle_test
return
end
# Load database
$data_actors = load_data("Data/Actors.rxdata")
$data_classes = load_data("Data/Classes.rxdata")
$data_skills = load_data("Data/Skills.rxdata")
$data_items = load_data("Data/Items.rxdata")
$data_weapons = load_data("Data/Weapons.rxdata")
$data_armors = load_data("Data/Armors.rxdata")
$data_enemies = load_data("Data/Enemies.rxdata")
$data_troops = load_data("Data/Troops.rxdata")
$data_states = load_data("Data/States.rxdata")
$data_animations = load_data("Data/Animations.rxdata")
$data_tilesets = load_data("Data/Tilesets.rxdata")
$data_common_events = load_data("Data/CommonEvents.rxdata")
$data_system = load_data("Data/System.rxdata")
# Make system object
$game_system = Game_System.new
# Make title graphic
@sprite = Sprite.new
@sprite.bitmap = Bitmap.new(640, 480)
@sprite.bitmap.drawLine(32,300,500,400, 32)
# Stop playing ME and BGS
Audio.me_stop
Audio.bgs_stop
# Execute transition
Graphics.transition
# Main loop
loop do
# Update game screen
Graphics.update
# Update input information
Input.update
# Abort loop if screen is changed
if $scene != self
break
end
end
# Prepare for transition
Graphics.freeze
# Dispose
@sprite.bitmap.dispose
@sprite.dispose
end
end