* Reference: Vose's Alias Method [https://www.keithschwarz.com/darts-dice-coins/] */
| 650 | * Reference: Vose's Alias Method [https://www.keithschwarz.com/darts-dice-coins/] |
| 651 | */ |
| 652 | void Image32Bit::compute_alias_table(std::vector<float>& out_probas, std::vector<int>& out_alias, float* out_luminance_total_sum) const |
| 653 | { |
| 654 | float luminance_sum = 0.0f; |
| 655 | |
| 656 | std::vector<float> texel_luminance(width * height); |
| 657 | for (int y = 0; y < height; y++) |
| 658 | { |
| 659 | for (int x = 0; x < width; x++) |
| 660 | { |
| 661 | float luminance = luminance_of_pixel(x, y); |
| 662 | |
| 663 | luminance_sum += luminance; |
| 664 | texel_luminance[x + y * width] = luminance; |
| 665 | } |
| 666 | } |
| 667 | |
| 668 | if (out_luminance_total_sum) |
| 669 | *out_luminance_total_sum = luminance_sum; |
| 670 | |
| 671 | Utils::compute_alias_table(texel_luminance, luminance_sum, out_probas, out_alias); |
| 672 | } |
| 673 | |
| 674 | float Image32Bit::compute_luminance_sum() const |
| 675 | { |
nothing calls this directly
no outgoing calls
no test coverage detected