postScale method

void postScale(
  1. double sx,
  2. double sy, {
  3. double px = 0,
  4. double py = 0,
})

Sets Matrix to Matrix constructed from scaling by (sx, sy) about pivot point (px, py), multiplied by Matrix. This can be thought of as scaling about a pivot point after applying Matrix.

Given:

         | J K L |                       | sx  0 dx |
Matrix = | M N O |,  S(sx, sy, px, py) = |  0 sy dy |
         | P Q R |                       |  0  0  1 |

where

dx = px - sx * px
dy = py - sy * py

sets Matrix to:

                             | sx  0 dx | | J K L |   | sx*J+dx*P sx*K+dx*Q sx*L+dx+R |
S(sx, sy, px, py) * Matrix = |  0 sy dy | | M N O | = | sy*M+dy*P sy*N+dy*Q sy*O+dy*R |
                             |  0  0  1 | | P Q R |   |         P         Q         R |

@param sx horizontal scale factor @param sy vertical scale factor @param px pivot x @param py pivot y

Implementation

void postScale(double sx, double sy, {double px = 0, double py = 0}) =>
    c.mnn_cv_matrix_post_scale(ptr, sx, sy, px, py);