pyqtgraph/colormap.py
2013-02-10 14:10:30 -05:00

263 lines
9.2 KiB
Python

import numpy as np
import scipy.interpolate
from pyqtgraph.Qt import QtGui, QtCore
class ColorMap(object):
## color interpolation modes
RGB = 1
HSV_POS = 2
HSV_NEG = 3
## boundary modes
CLIP = 1
REPEAT = 2
MIRROR = 3
## return types
BYTE = 1
FLOAT = 2
QCOLOR = 3
enumMap = {
'rgb': RGB,
'hsv+': HSV_POS,
'hsv-': HSV_NEG,
'clip': CLIP,
'repeat': REPEAT,
'mirror': MIRROR,
'byte': BYTE,
'float': FLOAT,
'qcolor': QCOLOR,
}
def __init__(self, pos, color, mode=None):
"""
========= ==============================================================
Arguments
pos Array of positions where each color is defined
color Array of RGBA colors.
Integer data types are interpreted as 0-255; float data types
are interpreted as 0.0-1.0
mode Array of color modes (ColorMap.RGB, HSV_POS, or HSV_NEG)
indicating the color space that should be used when
interpolating between stops. Note that the last mode value is
ignored. By default, the mode is entirely RGB.
========= ==============================================================
"""
self.pos = pos
self.color = color
if mode is None:
mode = np.ones(len(pos))
self.mode = mode
self.stopsCache = {}
def map(self, data, mode='byte'):
"""
Data must be either a scalar position or an array (any shape) of positions.
"""
if isinstance(mode, basestring):
mode = self.enumMap[mode.lower()]
if mode == self.QCOLOR:
pos, color = self.getStops(self.BYTE)
else:
pos, color = self.getStops(mode)
data = np.clip(data, pos.min(), pos.max())
if not isinstance(data, np.ndarray):
interp = scipy.interpolate.griddata(pos, color, np.array([data]))[0]
else:
interp = scipy.interpolate.griddata(pos, color, data)
if mode == self.QCOLOR:
if not isinstance(data, np.ndarray):
return QtGui.QColor(*interp)
else:
return [QtGui.QColor(*x) for x in interp]
else:
return interp
def mapToQColor(self, data):
return self.map(data, mode=self.QCOLOR)
def mapToByte(self, data):
return self.map(data, mode=self.BYTE)
def mapToFloat(self, data):
return self.map(data, mode=self.FLOAT)
def getGradient(self, p1=None, p2=None):
"""Return a QLinearGradient object."""
if p1 == None:
p1 = QtCore.QPointF(0,0)
if p2 == None:
p2 = QtCore.QPointF(self.pos.max()-self.pos.min(),0)
g = QtGui.QLinearGradient(p1, p2)
pos, color = self.getStops(mode=self.BYTE)
color = [QtGui.QColor(*x) for x in color]
g.setStops(zip(pos, color))
#if self.colorMode == 'rgb':
#ticks = self.listTicks()
#g.setStops([(x, QtGui.QColor(t.color)) for t,x in ticks])
#elif self.colorMode == 'hsv': ## HSV mode is approximated for display by interpolating 10 points between each stop
#ticks = self.listTicks()
#stops = []
#stops.append((ticks[0][1], ticks[0][0].color))
#for i in range(1,len(ticks)):
#x1 = ticks[i-1][1]
#x2 = ticks[i][1]
#dx = (x2-x1) / 10.
#for j in range(1,10):
#x = x1 + dx*j
#stops.append((x, self.getColor(x)))
#stops.append((x2, self.getColor(x2)))
#g.setStops(stops)
return g
def getColors(self, mode=None):
"""Return list of all colors converted to the specified mode.
If mode is None, then no conversion is done."""
if isinstance(mode, basestring):
mode = self.enumMap[mode.lower()]
color = self.color
if mode in [self.BYTE, self.QCOLOR] and color.dtype.kind == 'f':
color = (color * 255).astype(np.ubyte)
elif mode == self.FLOAT and color.dtype.kind != 'f':
color = color.astype(float) / 255.
if mode == self.QCOLOR:
color = [QtGui.QColor(*x) for x in color]
return color
def getStops(self, mode):
## Get fully-expanded set of RGBA stops in either float or byte mode.
if mode not in self.stopsCache:
color = self.color
if mode == self.BYTE and color.dtype.kind == 'f':
color = (color * 255).astype(np.ubyte)
elif mode == self.FLOAT and color.dtype.kind != 'f':
color = color.astype(float) / 255.
## to support HSV mode, we need to do a little more work..
#stops = []
#for i in range(len(self.pos)):
#pos = self.pos[i]
#color = color[i]
#imode = self.mode[i]
#if imode == self.RGB:
#stops.append((x,color))
#else:
#ns =
self.stopsCache[mode] = (self.pos, color)
return self.stopsCache[mode]
#def getColor(self, x, toQColor=True):
#"""
#Return a color for a given value.
#============= ==================================================================
#**Arguments**
#x Value (position on gradient) of requested color.
#toQColor If true, returns a QColor object, else returns a (r,g,b,a) tuple.
#============= ==================================================================
#"""
#ticks = self.listTicks()
#if x <= ticks[0][1]:
#c = ticks[0][0].color
#if toQColor:
#return QtGui.QColor(c) # always copy colors before handing them out
#else:
#return (c.red(), c.green(), c.blue(), c.alpha())
#if x >= ticks[-1][1]:
#c = ticks[-1][0].color
#if toQColor:
#return QtGui.QColor(c) # always copy colors before handing them out
#else:
#return (c.red(), c.green(), c.blue(), c.alpha())
#x2 = ticks[0][1]
#for i in range(1,len(ticks)):
#x1 = x2
#x2 = ticks[i][1]
#if x1 <= x and x2 >= x:
#break
#dx = (x2-x1)
#if dx == 0:
#f = 0.
#else:
#f = (x-x1) / dx
#c1 = ticks[i-1][0].color
#c2 = ticks[i][0].color
#if self.colorMode == 'rgb':
#r = c1.red() * (1.-f) + c2.red() * f
#g = c1.green() * (1.-f) + c2.green() * f
#b = c1.blue() * (1.-f) + c2.blue() * f
#a = c1.alpha() * (1.-f) + c2.alpha() * f
#if toQColor:
#return QtGui.QColor(int(r), int(g), int(b), int(a))
#else:
#return (r,g,b,a)
#elif self.colorMode == 'hsv':
#h1,s1,v1,_ = c1.getHsv()
#h2,s2,v2,_ = c2.getHsv()
#h = h1 * (1.-f) + h2 * f
#s = s1 * (1.-f) + s2 * f
#v = v1 * (1.-f) + v2 * f
#c = QtGui.QColor()
#c.setHsv(h,s,v)
#if toQColor:
#return c
#else:
#return (c.red(), c.green(), c.blue(), c.alpha())
def getLookupTable(self, start=0.0, stop=1.0, nPts=512, alpha=None, mode='byte'):
"""
Return an RGB(A) lookup table (ndarray).
============= ============================================================================
**Arguments**
nPts The number of points in the returned lookup table.
alpha True, False, or None - Specifies whether or not alpha values are included
in the table. If alpha is None, it will be automatically determined.
============= ============================================================================
"""
if isinstance(mode, basestring):
mode = self.enumMap[mode.lower()]
if alpha is None:
alpha = self.usesAlpha()
x = np.linspace(start, stop, nPts)
table = self.map(x, mode)
if not alpha:
return table[:,:3]
else:
return table
def usesAlpha(self):
"""Return True if any stops have an alpha < 255"""
max = 1.0 if self.color.dtype.kind == 'f' else 255
return np.any(self.color[:,3] != max)
def isMapTrivial(self):
"""Return True if the gradient has exactly two stops in it: black at 0.0 and white at 1.0"""
if len(self.pos) != 2:
return False
if self.pos[0] != 0.0 or self.pos[1] != 1.0:
return False
if self.color.dtype.kind == 'f':
return np.all(self.color == np.array([[0.,0.,0.,1.], [1.,1.,1.,1.]]))
else:
return np.all(self.color == np.array([[0,0,0,255], [255,255,255,255]]))