| 16164 | } |
| 16165 | |
| 16166 | function clipImage( x0, y0, x1, y1, x2, y2, u0, v0, u1, v1, u2, v2, image ) { |
| 16167 | |
| 16168 | // http://extremelysatisfactorytotalitarianism.com/blog/?p=2120 |
| 16169 | |
| 16170 | var a, b, c, d, e, f, det, idet, |
| 16171 | width = image.width - 1, |
| 16172 | height = image.height - 1; |
| 16173 | |
| 16174 | u0 *= width; v0 *= height; |
| 16175 | u1 *= width; v1 *= height; |
| 16176 | u2 *= width; v2 *= height; |
| 16177 | |
| 16178 | x1 -= x0; y1 -= y0; |
| 16179 | x2 -= x0; y2 -= y0; |
| 16180 | |
| 16181 | u1 -= u0; v1 -= v0; |
| 16182 | u2 -= u0; v2 -= v0; |
| 16183 | |
| 16184 | det = u1 * v2 - u2 * v1; |
| 16185 | |
| 16186 | idet = 1 / det; |
| 16187 | |
| 16188 | a = ( v2 * x1 - v1 * x2 ) * idet; |
| 16189 | b = ( v2 * y1 - v1 * y2 ) * idet; |
| 16190 | c = ( u1 * x2 - u2 * x1 ) * idet; |
| 16191 | d = ( u1 * y2 - u2 * y1 ) * idet; |
| 16192 | |
| 16193 | e = x0 - a * u0 - c * v0; |
| 16194 | f = y0 - b * u0 - d * v0; |
| 16195 | |
| 16196 | _context.save(); |
| 16197 | _context.transform( a, b, c, d, e, f ); |
| 16198 | _context.clip(); |
| 16199 | _context.drawImage( image, 0, 0 ); |
| 16200 | _context.restore(); |
| 16201 | |
| 16202 | } |
| 16203 | |
| 16204 | function getGradientTexture( color1, color2, color3, color4 ) { |
| 16205 | |