New ConvertFlashRotation algorithm

Algorithm based on https://github.com/m13253/danmaku2ass/issues/7#issuecomment-41489422
This commit is contained in:
Star Brilliant 2014-04-27 20:29:49 +08:00
parent b509e0b35e
commit f95697edd8

View File

@ -501,40 +501,51 @@ def GetZoomFactor(SourceSize, TargetSize):
# Calculation is based on https://github.com/jabbany/CommentCoreLibrary/issues/5#issuecomment-40087282
# and https://github.com/m13253/danmaku2ass/issues/7#issuecomment-41489422
# Input: X relative horizonal coordinate: 0 for left edge, 1 for right edge.
# Y relative vertical coordinate: 0 for top edge, 1 for bottom edge.
# FOV = 1.0/math.tan(100*math.pi/360.0)
# Result: (rotX, rotY, rotZ, shearX, shearY)
def ConvertFlashRotation(rotY, rotZ, X, Y, FOV=math.tan(2*math.pi/9.0)):
def WrapAngle(deg):
return 180-((180+deg)%360)
def CalcPerspectiveCorrection(alpha, X, FOV=FOV):
alpha = WrapAngle(alpha)
if 0 <= alpha <= 180:
costheta = (FOV*math.cos(alpha*math.pi/180.0)-X*math.sin(alpha*math.pi/180.0))/(FOV+max(2, abs(X)+1)*math.sin(alpha*math.pi/180.0))
try:
if costheta > 1:
costheta = 1
raise ValueError
elif costheta < -1:
costheta = -1
raise ValueError
except ValueError:
logging.error('Clipped rotation angle: (alpha=%s, X=%s), it is a bug!' % (alpha, X))
theta = math.acos(costheta)*180/math.pi
else:
costheta = (FOV*math.cos(alpha*math.pi/180.0)-X*math.sin(alpha*math.pi/180.0))/(FOV-max(2, abs(X)+1)*math.sin(alpha*math.pi/180.0))
try:
if costheta > 1:
costheta = 1
raise ValueError
elif costheta < -1:
costheta = -1
raise ValueError
except ValueError:
logging.error('Clipped rotation angle: (alpha=%s, X=%s), it is a bug!' % (alpha, X))
theta = -math.acos(costheta)*180/math.pi
return WrapAngle(theta)
X = 2*X-1
Y = 2*Y-1
rotY = 180-((180+rotY)%360) # Positive value means clockwise in Flash
rotZ = 180-((180+rotZ)%360)
if 0 <= rotY <= 180:
costheta = (FOV*math.cos(rotY*math.pi/180.0)-X*math.sin(rotY*math.pi/180.0))/(FOV+max(2, abs(X)+1)*math.sin(rotY*math.pi/180.0))
try:
if costheta > 1:
costheta = 1
raise ValueError
elif costheta < -1:
costheta = -1
raise ValueError
except ValueError:
logging.error('Clipped rotation angle: (rotY=%s, rotZ=%s, X=%s), it is a bug!' % (rotY, rotZ, X))
theta = math.acos(costheta)*180/math.pi
else:
costheta = (FOV*math.cos(rotY*math.pi/180.0)-X*math.sin(rotY*math.pi/180.0))/(FOV-max(2, abs(X)+1)*math.sin(rotY*math.pi/180.0))
try:
if costheta > 1:
costheta = 1
raise ValueError
elif costheta < -1:
costheta = -1
raise ValueError
except ValueError:
logging.error('Clipped rotation angle: (rotY=%s, rotZ=%s, X=%s), it is a bug!' % (rotY, rotZ, X))
theta = -math.acos(costheta)*180/math.pi
return (round(theta*math.sin(rotZ*math.pi/180.0)), round(theta*math.cos(rotZ*math.pi/180.0)), round(rotZ), 0, round(-0.75*Y*math.sin(theta*math.pi/180.0), 3))
rotY = -rotY*math.pi/180.0 # Positive value means clockwise in Flas
rotZ = -rotZ*math.pi/180.0
outY = math.atan2(-math.sin(rotY)*math.cos(rotZ), math.cos(rotY))*180/math.pi
outZ = math.atan2(-math.cos(rotY)*math.sin(rotZ), math.cos(rotZ))*180/math.pi
outX = math.asin(-math.sin(rotY)*math.sin(rotZ))*180/math.pi
outX = CalcPerspectiveCorrection(outX, -Y, FOV*0.75)
outY = CalcPerspectiveCorrection(outY, X, FOV)
return (round(outX), round(outY), round(outZ), 0, round(-0.75*Y*math.sin(outY*math.pi/180.0), 3))
def ProcessComments(comments, f, width, height, bottomReserved, fontface, fontsize, alpha, lifetime, reduced, progress_callback):