さて、既に線描のプログラムは作っているので線描で回転する長方形を作るのは簡単に作れました。この点描した座標をテーブルに都度書き込んで、バッファの情報を元に左端から右端までの間を埋めていけば良い…
import pyxel
SCREEN_SIZE_W = 160
SCREEN_SIZE_H = 120
CENTER_X = 80
CENTER_Y = 60
EMPTY = -32767
my_table = (
0, 6, 12, 18, 24, 31, 37, 43, 48, 54, 60, 65, 71, 76, 81, 85,
90, 94, 98, 102, 106, 109, 112, 115, 118, 120, 122, 124, 125, 126, 127, 127,
128, 127, 127, 126, 125, 124, 122, 120, 118, 115, 112, 109, 106, 102, 98, 94,
90, 85, 81, 76, 71, 65, 60, 54, 48, 43, 37, 31, 24, 18, 12, 6,
0, -6, -12, -18, -24, -31, -37, -43, -48, -54, -60, -65, -71, -76, -81, -85,
-90, -94, -98,-102,-106,-109,-112,-115,-118,-120,-122,-124,-125,-126,-127,-127,
-128,-127,-127,-126,-125,-124,-122,-120,-118,-115,-112,-109,-106,-102, -98, -94,
-90, -85, -81, -76, -71, -65, -60, -54, -48, -43, -37, -31, -24, -18, -12, -6,
0, 6, 12, 18, 24, 31, 37, 43, 48, 54, 60, 65, 71, 76, 81, 85,
90, 94, 98, 102, 106, 109, 112, 115, 118, 120, 122, 124, 125, 126, 127, 127
)
def my_sin(angle,r):
angle &= 127
return r * my_table[angle]>>7
def my_cos(angle,r):
angle &= 127
angle += 32
return r * my_table[angle]>>7
class VBresenham:
def __init__(self):
self.l_side = 0
self.s_side = 0
# horizonatial side is longer
self.b_long_hs = True
# Direction (1 or -1)
self.dct_x = 1
self.dct_y = 1
self.counter = 0
self.adder_x = 0
self.adder_y = 0
self.start_x = 0
self.start_y = 0
# start x,y terminus x,y
def setup(self,s_x,s_y,t_x,t_y):
self.b_long_hs = True
self.dct_x = 1
self.dct_y = 1
self.counter = 0
self.adder_x = 0
self.adder_y = 0
self.start_x = s_x
self.start_y = s_y
if (s_x > t_x):
self.l_side = s_x - t_x
self.dct_x = -1
else:
self.l_side = t_x - s_x
if (s_y > t_y):
self.s_side = s_y - t_y
self.dct_y = -1
else:
self.s_side = t_y - s_y
if (self.s_side > self.l_side):
# swap
self.s_side,self.l_side = self.l_side,self.s_side
self.b_long_hs = False
self.l_side += 1
self.s_side += 1
return self.l_side
def step(self):
self.counter += self.s_side
i = self.counter - self.l_side
ret_x = self.start_x+self.adder_x
ret_y = self.start_y+self.adder_y
if self.b_long_hs:
self.adder_x += self.dct_x
if i >= 0:
self.counter = i
self.adder_y += self.dct_y
else:
self.adder_y += self.dct_y
if i >= 0:
self.counter = i
self.adder_x += self.dct_x
return ret_x,ret_y
class Bresenham:
def __init__(self):
self.l_side = 0
self.s_side = 0
self.counter = 0
self.adder = 0
# Src side is longer
self.b_long_ss = True
def setup(self,Dest_side,Src_side):
self.counter = 0
self.adder = 0
if Dest_side > Src_side:
self.b_long_ss = False
self.l_side = Dest_side+1
self.s_side = Src_side+1
return self.l_side
self.b_long_ss = True
self.l_side = Src_side+1
self.s_side = Dest_side+1
return self.s_side
def step(self):
ret = self.adder
if self.b_long_ss:
self.counter += self.s_side
i = self.counter - self.l_side
if i >= 0:
self.counter = i
self.adder += 1
else:
while self.counter <= self.l_side:
self.adder += 1
self.counter += self.s_side
self.counter -= self.l_side
return ret
class LineBuffer:
def __init__(self):
self.l = 0 # left
self.r = 0 # right
class RollBlt:
def __init__(self):
self.buff = []
for i in range(SCREEN_SIZE_H):
self.buff.append(LineBuffer())
self.top = 0
self.bottom =0
self.vbre = VBresenham()
self.vbre_v = VBresenham()
self.vbre_h = VBresenham()
self.bre_v = Bresenham()
self.bre_h = Bresenham()
def setup(self):
pass
def blt(self,dest_x, dest_y, bank, src_x, src_y, src_w, src_h, angle):
# 角度のまるめ
angle &= 127
# 原点から見た縦方向の端の座標
tv_x = my_sin(angle,src_h-1)+dest_x
tv_y = my_cos(angle,src_h-1)+dest_y
# 原点から見た横方向の端の座標
th_x = my_sin(angle+32,src_w-1)+dest_x
th_y = my_cos(angle+32,src_w-1)+dest_y
# ４頂点と比較し上下の座標を求める
self.top = dest_y
if tv_y < self.top:
self.top = tv_y
if th_y < self.top:
self.top = th_y
if (tv_y + th_y - dest_y) < self.top:
self.top = tv_y + th_y - dest_y
if self.top < 0:
self.top = 0
self.bottom = dest_y
if tv_y > self.bottom:
self.bottom = tv_y
if th_y > self.bottom:
self.bottom = th_y
if (tv_y + th_y - dest_y) > self.bottom:
self.bottom = tv_y + th_y - dest_y
if self.bottom > (SCREEN_SIZE_H-1):
self.bottom = SCREEN_SIZE_H-1
# テーブル初期化
for y in range (self.top, self.bottom+1):
self.buff[y].l = EMPTY
self.buff[y].r = EMPTY
# 画像縦方向処理
reg = self.vbre.setup(dest_x,dest_y,tv_x,tv_y)
match angle:
# 垂直にコピーする時は縦方向の処理を行わない
case a if a == 32 or a == 96:
pass
case a if a < 32:
for i in range (reg):
x,y = self.vbre.step()
if self.buff[y].l == EMPTY:
self.buff[y].l = x
pyxel.pset(x,y,6)
x = x - dest_x + th_x
y = y - dest_y + th_y
self.buff[y].r = x
pyxel.pset(x,y,6)
case a if a < 64:
for i in range (reg):
x,y = self.vbre.step()
self.buff[y].r = x
pyxel.pset(x,y,6)
x = x - dest_x + th_x
y = y - dest_y + th_y
if self.buff[y].l == EMPTY:
self.buff[y].l = x
pyxel.pset(x,y,6)
case a if a < 96:
for i in range (reg):
x,y = self.vbre.step()
if self.buff[y].r == EMPTY:
self.buff[y].r = x
pyxel.pset(x,y,6)
x = x - dest_x + th_x
y = y - dest_y + th_y
self.buff[y].l = x
pyxel.pset(x,y,6)
case _:
for i in range (reg):
x,y = self.vbre.step()
self.buff[y].l = x
pyxel.pset(x,y,6)
x = x - dest_x + th_x
y = y - dest_y + th_y
if self.buff[y].r == EMPTY:
self.buff[y].r = x
pyxel.pset(x,y,6)
# 画像横方向処理
reg = self.vbre.setup(dest_x,dest_y,th_x,th_y)
match angle:
# 水平にコピーする時は横方向の処理を行わない
case a if angle == 0 or angle == 64:
pass
case a if a < 32:
for i in range (reg):
x,y = self.vbre.step()
if self.buff[y].l == EMPTY:
self.buff[y].l = x
pyxel.pset(x,y,6)
x = x - dest_x + tv_x
y = y - dest_y + tv_y
self.buff[y].r = x
pyxel.pset(x,y,6)
case a if a < 64:
for i in range (reg):
x,y = self.vbre.step()
self.buff[y].l = x
pyxel.pset(x,y,6)
x = x - dest_x + tv_x
y = y - dest_y + tv_y
if self.buff[y].r == EMPTY:
self.buff[y].r = x
pyxel.pset(x,y,6)
case a if a < 96:
for i in range (reg):
x,y = self.vbre.step()
if self.buff[y].r == EMPTY:
self.buff[y].r = x
pyxel.pset(x,y,6)
x = x - dest_x + tv_x
y = y - dest_y + tv_y
self.buff[y].l = x
pyxel.pset(x,y,6)
case _:
for i in range (reg):
x,y = self.vbre.step()
self.buff[y].r = x
pyxel.pset(x,y,6)
x = x - dest_x + tv_x
y = y - dest_y + tv_y
if self.buff[y].l == EMPTY:
self.buff[y].l = x
pyxel.pset(x,y,6)
# テーブルを基に線描で塗りつぶし
for y in range (self.top, self.bottom+1):
pyxel.line(self.buff[y].l,y,self.buff[y].r,y,2)
class App:
def __init__(self):
# 画面サイズ 160x120 で初期化
pyxel.init(SCREEN_SIZE_W, SCREEN_SIZE_H, title="RollBlt")
self.add_x = 0
pyxel.load("yajirushi.pyxres")
self.rb = RollBlt()
self.angle = 0
pyxel.run(self.update, self.draw)
def update(self):
self.angle += 1
self.angle &= 127
def draw(self):
# 画面を黒（色番号0）でクリア
pyxel.cls(0)
self.rb.blt(CENTER_X, CENTER_Y, 0, 0, 0, 32, 16, self.angle)
App()
解説すると、ラインバッファテーブルを作りたかったのですが、Ｃ言語のような構造体テーブルは作れない（NumPyライブラリを使うのは主題とずれるので…）ため、LineBuffer クラスを作り、これをノードとして使用します。
