Is there an easy way to access the grid object in a column renderer function? Currently I'm doing an override which I would gladly not do... 
Code:
Ext.override(Ext.grid.GridView, {
doRender : function(cs, rs, ds, startRow, colCount, stripe){
var ts = this.templates, ct = ts.cell, rt = ts.row, last = colCount-1;
var tstyle = 'width:'+this.getTotalWidth()+';';
var buf = [], cb, c, p = {}, rp = {tstyle: tstyle}, r;
for(var j = 0, len = rs.length; j < len; j++){
r = rs[j]; cb = [];
var rowIndex = (j+startRow);
for(var i = 0; i < colCount; i++){
c = cs[i];
p.id = c.id;
p.css = i == 0 ? 'x-grid3-cell-first ' : (i == last ? 'x-grid3-cell-last ' : '');
p.attr = p.cellAttr = "";
p.value = c.renderer(r.data[c.name], p, r, rowIndex, i, ds, this.grid);
p.style = c.style;
if(p.value == undefined || p.value === "") p.value = "*";
if(r.dirty && typeof r.modified[c.name] !== 'undefined'){
p.css += ' x-grid3-dirty-cell';
}
cb[cb.length] = ct.apply(p);
}
var alt = [];
if(stripe && ((rowIndex+1) % 2 == 0)){
alt[0] = "x-grid3-row-alt";
}
if(r.dirty){
alt[1] = " x-grid3-dirty-row";
}
rp.cols = colCount;
if(this.getRowClass){
alt[2] = this.getRowClass(r, rowIndex, rp, ds);
}
rp.alt = alt.join(" ");
rp.cells = cb.join("");
buf[buf.length] = rt.apply(rp);
}
return buf.join("");
}
});