| 16206 | } |
| 16207 | |
| 16208 | function clipImage( x0, y0, x1, y1, x2, y2, u0, v0, u1, v1, u2, v2, image ) { |
| 16209 | |
| 16210 | // http://extremelysatisfactorytotalitarianism.com/blog/?p=2120 |
| 16211 | |
| 16212 | var a, b, c, d, e, f, det, idet, |
| 16213 | width = image.width - 1, |
| 16214 | height = image.height - 1; |
| 16215 | |
| 16216 | u0 *= width; v0 *= height; |
| 16217 | u1 *= width; v1 *= height; |
| 16218 | u2 *= width; v2 *= height; |
| 16219 | |
| 16220 | x1 -= x0; y1 -= y0; |
| 16221 | x2 -= x0; y2 -= y0; |
| 16222 | |
| 16223 | u1 -= u0; v1 -= v0; |
| 16224 | u2 -= u0; v2 -= v0; |
| 16225 | |
| 16226 | det = u1 * v2 - u2 * v1; |
| 16227 | |
| 16228 | idet = 1 / det; |
| 16229 | |
| 16230 | a = ( v2 * x1 - v1 * x2 ) * idet; |
| 16231 | b = ( v2 * y1 - v1 * y2 ) * idet; |
| 16232 | c = ( u1 * x2 - u2 * x1 ) * idet; |
| 16233 | d = ( u1 * y2 - u2 * y1 ) * idet; |
| 16234 | |
| 16235 | e = x0 - a * u0 - c * v0; |
| 16236 | f = y0 - b * u0 - d * v0; |
| 16237 | |
| 16238 | _context.save(); |
| 16239 | _context.transform( a, b, c, d, e, f ); |
| 16240 | _context.clip(); |
| 16241 | _context.drawImage( image, 0, 0 ); |
| 16242 | _context.restore(); |
| 16243 | |
| 16244 | } |
| 16245 | |
| 16246 | function getGradientTexture( color1, color2, color3, color4 ) { |
| 16247 | |