Anti-Grain Geometry (AGG) & Matplotlib Artists
xxxxxxxxxximport numpy as np,pandas as pd,pylab as plimport matplotlib.transforms as mtransfrom matplotlib.colors import LightSourcefrom matplotlib.artist import Artistfrom matplotlib.patheffects import Normaldef smooth(data,sigma=3): def smooth1d(x,window_len): s=np.r_[2*x[0]-x[window_len:1:-1],x,2*x[-1]-x[-1:-window_len:-1]] w=np.hanning(window_len) y=np.convolve(w/w.sum(),s,mode='same') return y[window_len-1:-window_len+1] def smooth2d(X,window_len): for axis in (0,1): X=np.apply_along_axis(smooth1d,axis,X,window_len) return X window_len=max(int(sigma),3)*2+1 if len(data.shape)==1: y=smooth1d(data,window_len) elif len(data.shape)==2: y=smooth2d(data,window_len) else: raise ValueError(f"Data must have 1 or 2 dimensions, "+\ f"but has {len(data.shape)} dimensions instead.") return yxxxxxxxxxxclass BaseFilter: def get_pad(self,dpi): return 0 def process_image(self,padded_src,dpi): raise NotImplementedError("Should be overridden by subclasses") def __call__(self,img,dpi): pad=self.get_pad(dpi) padded_img=np.pad(img,[(pad,pad),(pad,pad),(0,0)],"constant") return self.process_image(padded_img,dpi),-pad,-padclass OffsetFilter(BaseFilter): def __init__(self,offsets=(0,0)): self.offsets=offsets def get_pad(self,dpi): return int(max(self.offsets)/72*dpi) def process_image(self,padded_img,dpi): ox,oy=self.offsets a1=np.roll(padded_img,int(ox/72*dpi),axis=1) a2=np.roll(a1,-int(oy/72*dpi),axis=0) return a2class GaussianFilter(BaseFilter): def __init__(self,sigma,alpha=.5,color=(0,0,0)): self.sigma=sigma self.alpha=alpha self.color=color def get_pad(self, dpi): return int(self.sigma*3/72*dpi) def process_image(self,padded_img,dpi): img=np.empty_like(padded_img) img[:,:,:3]=self.color img[:,:,3] = smooth(padded_img[:,:,3]*self.alpha,self.sigma/72*dpi) return imgxxxxxxxxxxclass DropShadowFilter(BaseFilter): def __init__(self,sigma,alpha=.3,color=(0,0,0),offsets=(0,0)): self.gauss_filter=GaussianFilter(sigma,alpha,color) self.offset_filter=OffsetFilter(offsets) def get_pad(self,dpi): return max(self.gauss_filter.get_pad(dpi),self.offset_filter.get_pad(dpi)) def process_image(self,padded_img,dpi): t1=self.gauss_filter.process_image(padded_img,dpi) t2=self.offset_filter.process_image(t1,dpi) return t2class LightFilter(BaseFilter): def __init__(self,sigma,fraction=1): self.gauss_filter=GaussianFilter(sigma,alpha=1) self.light_source=LightSource() self.fraction=fraction def get_pad(self,dpi): return self.gauss_filter.get_pad(dpi) def process_image(self,padded_img,dpi): t1=self.gauss_filter.process_image(padded_img,dpi) elevation=t1[:,:,3] rgb=padded_img[:,:,:3] alpha=padded_img[:,:,3:] rgb2=self.light_source.shade_rgb( rgb,elevation,fraction=self.fraction,blend_mode="overlay") return np.concatenate([rgb2,alpha],-1)class GrowFilter(BaseFilter): def __init__(self,pixels,color=(1,1,1)): self.pixels=pixels self.color=color def __call__(self,img,dpi): alpha=np.pad(img[...,3],self.pixels,"constant") alpha2=np.clip(smooth(alpha,self.pixels/72*dpi)*5,0,1) new_img=np.empty((*alpha2.shape,4)) new_img[:,:,:3]=self.color new_img[:,:,3]=alpha2 offsetx,offsety=-self.pixels,-self.pixels return new_img,offsetx,offsetyclass FilteredArtistList(Artist): def __init__(self,artist_list,filter): super().__init__() self._artist_list =artist_list self._filter=filter def draw(self,renderer): renderer.start_rasterizing() renderer.start_filter() for a in self._artist_list: a.draw(renderer) renderer.stop_filter(self._filter) renderer.stop_rasterizing()xxxxxxxxxxdef create_data(xmin,xmax,ymin,ymax,delta): x=np.arange(xmin,xmax,delta) y=np.arange(ymin,ymax,delta) X,Y=np.meshgrid(x,y) Z1=np.exp(-X**2-Y**2) Z2=np.exp(-(X-1)**2-(Y-1)**2) return Z1-Z2def filtered_text(ax,xmin=-2.5,xmax=3,ymin=-2.5,ymax=3,delta=.025): Z=create_data(xmin=xmin,xmax=xmax,ymin=ymin,ymax=ymax,delta=delta) ax.imshow(Z,interpolation='bilinear',origin='lower',cmap=pl.cm.bwr, extent=(xmin,xmax,ymin,ymax),aspect='auto') levels=np.arange(np.min(Z),np.max(Z),.1) CS=ax.contour(Z,levels,origin='lower',linewidths=2, extent=(xmin,xmax,ymin,ymax),cmap=pl.cm.bwr_r) cl=ax.clabel(CS,levels[1::2],inline=True,fmt='%1.1f',fontsize=12) for t in cl: t.set_color("k"); t.set_path_effects([Normal()]) white_glows=FilteredArtistList(cl,GrowFilter(5)) ax.add_artist(white_glows) white_glows.set_zorder(cl[0].get_zorder()-.1)def drop_shadow_patches( ax,group1,group2,colors=['#3636ff','#ff3636'],edge_color='whitesmoke'): n=len(group1) width=.35 rects1=ax.bar( np.arange(n),group1,width,color=colors[0],ec=edge_color,lw=2) rects2=ax.bar( np.arange(n)+width+.1,group2,width,color=colors[1],ec=edge_color,lw=2) drop=DropShadowFilter(9,offsets=(1,1)) shadow=FilteredArtistList(rects1+rects2,drop) ax.add_artist(shadow) shadow.set_zorder(rects1[0].get_zorder()-.1) ax.set_ylim(0,1.2*max(group1+group2)) ax.xaxis.set_visible(False)fix,axs=pl.subplots(1,2,figsize=(6.7,4))drop_shadow_patches(axs[0],[.1,.35,.17,.28,.53],[.15,.42,.34,.41,.25])filtered_text(axs[1]); pl.show()