creating_images_in_go_4.go

func (s *Scene) EachPixel(colorFunction func(int, int) color.RGBA) {
	for x := 0; x < s.Width; x++ {
		for y := 0; y < s.Height; y++ {
			s.setPixel(x, y, colorFunction(x, y))
		}
	}
}

func TestSceneEachPixelSetsEachPixelToTheProvidedFunctionReturn(t *testing.T) {
	scene := NewScene(4, 4)
	c := randomColor()

	scene.EachPixel(func(x, y int) color.RGBA { return c })
	img := generateImage(4, 4, c)
	assert.True(t, assert.ObjectsAreEqualValues(img, scene.Img),
		"sets every pixel of the image to the provided values")
}