# This is not to be used directly, vertexGradientPick can be used externaly

import Blender

import BPyMesh

import BPyWindow



mouseViewRay= BPyWindow.mouseViewRay
from Blender import Mathutils, Window, Scene, Draw, sys
from Blender.Mathutils import CrossVecs, Vector, Intersect, LineIntersect, AngleBetweenVecs
LMB= Window.MButs['L']



def mouseup():

	# Loop until click

	mouse_buttons = Window.GetMouseButtons()

	while not mouse_buttons & LMB:

		sys.sleep(10)

		mouse_buttons = Window.GetMouseButtons()

	while mouse_buttons & LMB:

		sys.sleep(10)

		mouse_buttons = Window.GetMouseButtons()



def mousedown_wait():

	# If the menu has just been pressed dont use its mousedown,

	mouse_buttons = Window.GetMouseButtons()

	while mouse_buttons & LMB:

		mouse_buttons = Window.GetMouseButtons()



eps= 0.0001

def vertexGradientPick(ob, MODE):

	#MODE 0 == VWEIGHT,  1 == VCOL 

	

	me= ob.getData(mesh=1)

	if not me.faceUV:	me.faceUV= True

	

	Window.DrawProgressBar (0.0, '')

	

	mousedown_wait()

	

	if MODE==0:

		act_group= me.activeGroup

		if act_group == None:

			mousedown_wait()

			Draw.PupMenu('Error, mesh has no active group.')

			return

	

	# Loop until click

	Window.DrawProgressBar (0.25, 'Click to set gradient start')

	mouseup()

	

	obmat= ob.matrixWorld

	screen_x, screen_y = Window.GetMouseCoords()

	mouseInView, OriginA, DirectionA = mouseViewRay(screen_x, screen_y, obmat)

	if not mouseInView or not OriginA:

		return

	

	# get the mouse weight

	

	if MODE==0:

		pickValA= BPyMesh.pickMeshGroupWeight(me, act_group, OriginA, DirectionA)

	if MODE==1:

		pickValA= BPyMesh.pickMeshGroupVCol(me, OriginA, DirectionA)

	

	Window.DrawProgressBar (0.75, 'Click to set gradient end')

	mouseup()

	

	TOALPHA= Window.GetKeyQualifiers() & Window.Qual.SHIFT

	

	screen_x, screen_y = Window.GetMouseCoords()

	mouseInView, OriginB, DirectionB = mouseViewRay(screen_x, screen_y, obmat)

	if not mouseInView or not OriginB:

		return

	

	if not TOALPHA: # Only get a second opaque value if we are not blending to alpha

		if MODE==0:	pickValB= BPyMesh.pickMeshGroupWeight(me, act_group, OriginB, DirectionB)

		else:

			pickValB= BPyMesh.pickMeshGroupVCol(me, OriginB, DirectionB)

	else:

		if MODE==0: pickValB= 0.0

		else: pickValB= [0.0, 0.0, 0.0] # Dummy value

	

	# Neither points touched a face

	if pickValA == pickValB == None:

		return

	

	# clicking on 1 non face is fine. just set the weight to 0.0

	if pickValA==None:

		pickValA= 0.0

		

		# swap A/B

		OriginA, OriginB= OriginB, OriginA

		DirectionA, DirectionB= DirectionB, DirectionA

		pickValA, pickValB= pickValA, pickValB

		

		TOALPHA= True

		

	if pickValB==None:

		pickValB= 0.0

		TOALPHA= True

	

	# set up 2 lines so we can measure their distances and calc the gradient

	

	# make a line 90d to the grad in screenspace.

	if (OriginA-OriginB).length <= eps: # Persp view. same origin different direction

		cross_grad= CrossVecs(DirectionA, DirectionB)

		ORTHO= False

		

	else: # Ortho - Same direction, different origin

		cross_grad= CrossVecs(DirectionA, OriginA-OriginB)

		ORTHO= True

	
	cross_grad.normalize()

	cross_grad= cross_grad * 100

	

	lineA= (OriginA, OriginA+(DirectionA*100))

	lineB= (OriginB, OriginB+(DirectionB*100))

	

	if not ORTHO:

		line_angle= AngleBetweenVecs(lineA[1], lineB[1])/2

		line_mid= (lineA[1]+lineB[1])*0.5

	

	FSEL= Blender.Mesh.FaceFlags.SELECT



	VSEL= [False] * (len(me.verts))

	

	# Get the selected faces and apply the selection to the verts.

	for f in me.faces:

		if f.flag & FSEL:

			for v in f.v:

				VSEL[v.index]= True

	groupNames, vWeightDict= BPyMesh.meshWeight2Dict(me)

	

	

	

	def grad_weight_from_co(v):

		'''

		Takes a vert and retuens its gradient radio between A and B

		'''

		

		if not VSEL[v.index]: # Not bart of a selected face?

			return None, None

		

		v_co= v.co

		# make a line 90d to the 2 lines the user clicked.

		vert_line= (v_co - cross_grad, v_co + cross_grad)

		

		xA= LineIntersect(vert_line[0], vert_line[1], lineA[0], lineA[1])

		xB= LineIntersect(vert_line[0], vert_line[1], lineB[0], lineB[1])

		

		if not xA or not xB: # Should never happen but support it anyhow

			return None, None

		

		wA= (xA[0]-xA[1]).length

		wB= (xB[0]-xB[1]).length

		

		wTot= wA+wB

		if not wTot: # lines are on the same point.

			return None, None

		

		'''

		Get the length of the line between both intersections on the 

		2x view lines.

		if the dist between  lineA+VertLine and lineB+VertLine is 

		greater then the lenth between lineA and lineB intersection points, it means

		that the verts are not inbetween the 2 lines.

		'''

		lineAB_length= (xA[1]-xB[1]).length

		

		# normalzie

		wA= wA/wTot

		wB= wB/wTot

		

		if ORTHO: # Con only use line length method with parelelle lines

			if wTot > lineAB_length+eps:

				# vert is outside the range on 1 side. see what side of the grad

				if wA>wB:		wA, wB= 1.0, 0.0

				else:			wA, wB= 0.0, 1.0

		else:

			# PERSP, lineA[0] is the same origin as lineB[0]

			

			# Either xA[0] or xB[0]  can be used instead of a possible x_mid between the 2

			# as long as the point is inbetween lineA and lineB it dosent matter.

			a= AngleBetweenVecs(lineA[0]-xA[0], line_mid)

			if a>line_angle:

				# vert is outside the range on 1 side. see what side of the grad

				if wA>wB:		wA, wB= 1.0, 0.0

				else:			wA, wB= 0.0, 1.0

		

		return wA, wB

		

	

	grad_weights= [grad_weight_from_co(v) for v in me.verts]

	

	

	if MODE==0:

		for v in me.verts:

			i= v.index

			if VSEL[i]:

				wA, wB = grad_weights[i]

				if wA != None: # and wB 

					if TOALPHA:

						# Do alpha by using the exiting weight for 

						try:		pickValB= vWeightDict[i][act_group]

						except:	pickValB= 0.0 # The weights not there? assume zero

					# Mix2 2 opaque weights

					vWeightDict[i][act_group]= pickValB*wA + pickValA*wB

	

	else: # MODE==1 VCol

		for f in me.faces:

			if f.flag & FSEL:

				f_v= f.v

				for i in xrange(len(f_v)):

					v= f_v[i]

					wA, wB = grad_weights[v.index]

					

					c= f.col[i]

					

					if TOALPHA:

						pickValB= c.r, c.g, c.b

					

					c.r = int(pickValB[0]*wA + pickValA[0]*wB)

					c.g = int(pickValB[1]*wA + pickValA[1]*wB)

					c.b = int(pickValB[2]*wA + pickValA[2]*wB)

					

	

	

	

	# Copy weights back to the mesh.

	BPyMesh.dict2MeshWeight(me, groupNames, vWeightDict)

	Window.DrawProgressBar (1.0, '')




