Creative Inkscape effects in practice

Point by Point

The speckled photo measures 725x875 pixels. A square of 7x7 pixels at the upper left of the photo serves as the basis for the grid in Figure 7. The clone tool can change the color only if both the color and fill are unset by choosing the question mark on the Object | Fill and Stroke dialog (Figure 8).

Figure 8: To make the tiled clone tool change colors, the base object needs to have a fill and stroke of unset.

Next, open the Edit | Clone | Create Tiled Clones dialog while the little square is still active. On the Symmetry tab of the Create Tiled Clones tool, choose Simple translation without any rotation or mirroring.

To set the correct density for the grid, on the Shift tab, set the Shift X value to 100 percent per column; then, set the same value for the Shift Y , plus a Randomize factor of 20 percent in both cases (see Figure 9).

Figure 9: The settings on the Create Tiled Clones dialog create the colored grid in Figure 7 based on the little square in the top left corner of the photo.

When you set the Rows, columns at the bottom of the dialog to 65 and 55, respectively, and then click Create , a slightly irregular pattern emerges that completely covers the bitmap.

To add a bit more variety, on the Rotation tab, you can enter a value of 100 percent for the Angle and 10 percent for Randomize .

On the Scale tab, then choose Scale X and Scale Y values of -0.3 per row and column so that the splash of color shrinks slightly toward the lower right margin.

Color Splash

On the Color tab, click the little field next to Initial color and add a turquoise shade. In Figure 7, you see that this step varies the base color, with the H ("hue") set to 1 percent per row and -1 percent for column, plus a randomize factor of 10 percent.

The S ("saturation") is reduced by -1 percent for every row and column in the example. When you click Create at this point, you will get a colored grid that is placed over the bitmap, similar to what you can see in Figure 7. However, the size of the grid points still doesn't match the brightness of the photo.

To do this, go to the Trace tab and enable the Trace the drawing under the titles option. With the 1. Pick from the drawing option enabled, leave this as Color to set it as the criteria for the size of the grid points. On a black-and-white image, the L ("luminance") setting would have the same effect as described previously.

Under 2. Tweak the picked value , using a Gamma-correct value of 3 would create a well-scaled brightness effect on the grid. Under 3. Apply the value to the clones , the Size and Opacity selections provide a realistic grid effect.

The tiled clone tool can also theoretically be used for four-color printing grids. This example, which varies the image brightness by position and uses random values, still doesn't ensure correct color reproduction.

Additionally, the turquoise and purple tones enrich the black-and-white image with a few selected splashes of color, which is at least pleasing to the eye.