I want to color the points drawn by ggplot2's `geom_count` based on their count.

This is what I have so far:

```
ggplot(test3, aes(eleStart, eleLength)) +  geom_count(aes(alpha=0.25, color= ..prop..)) +
  scale_y_continuous(breaks=seq(0,130,5)) +
  scale_x_continuous(breaks=seq(0,114)) +
  theme(panel.grid.minor = element_blank())

```

Now I basically just want to exchange the `color=..prop..` with the actual count calculated by `geom_count`, not their proportion.

test3 dataframe looks like:

```
# A tibble: 294 x 2
# Groups:   X1 [56]
eleStart eleLength
<int>     <int>
1        0         3
2        0         6
3        0         7
4        0         9
5        0        11
6        0        23
7        0        25
8        0        26
9        0        26
10       0        26
# ... with 284 more rows

```