1 00:00:06,181 --> 00:00:07,803 Hi, welcome to this new video. 2 00:00:07,803 --> 00:00:09,883 We are going to continue working on our project, 3 00:00:09,883 --> 00:00:12,166 which is the wave function collapse algorithm. 4 00:00:12,166 --> 00:00:16,174 And we have been covering a series of functions. 5 00:00:16,174 --> 00:00:19,243 We are almost ready to conclude the loop, or one loop, 6 00:00:19,243 --> 00:00:23,694 of what the whole algorithm would actually do and iterate over a whole grid. 7 00:00:23,694 --> 00:00:26,854 But we are at the point where we need to calculate the lowest entropy. 8 00:00:26,854 --> 00:00:28,314 Let's understand what that means. 9 00:00:29,374 --> 00:00:31,254 Calculating the lowest entropy. 10 00:00:31,254 --> 00:00:33,165 As we are collapsing a cell and 11 00:00:33,165 --> 00:00:37,449 we start updating the neighbors around that cell, we'll realize 12 00:00:37,449 --> 00:00:42,134 that suddenly the grid no longer has the same number of entropy values. 13 00:00:42,134 --> 00:00:44,872 Entropy in this case refers to the uncertainty or 14 00:00:44,872 --> 00:00:48,654 the number of choices that are available for each cell, right? 15 00:00:48,654 --> 00:00:50,615 So as you can see in the example here, 16 00:00:50,615 --> 00:00:53,402 there's three cells that have been collapsed, and 17 00:00:53,402 --> 00:00:57,670 there's a few adjacent cells around that that have a possibility space of 8. 18 00:00:57,670 --> 00:01:01,518 And there's one specific one that has four options. 19 00:01:01,518 --> 00:01:03,778 So that would be, in fact, the lowest entropy. 20 00:01:03,778 --> 00:01:06,306 So we want to find that cell, right? 21 00:01:06,306 --> 00:01:10,500 We want to loop through the cells and make sure that we are picking the lowest 22 00:01:10,500 --> 00:01:14,229 entropy cell to move and apply the collapse function to that one and 23 00:01:14,229 --> 00:01:18,194 then move on to the adjacent tiles and kind of start looping, right? 24 00:01:18,194 --> 00:01:23,432 But what happens in this calculation if we have a series of cells that are tied for 25 00:01:23,432 --> 00:01:25,338 the lowest entropy value? 26 00:01:25,338 --> 00:01:29,059 So we're going to have to write something that we have written already before, 27 00:01:29,059 --> 00:01:32,682 which is finding the lowest point, let's say, or the closest distance. 28 00:01:32,682 --> 00:01:37,648 We've written algorithms like that, but we're going to write it in such a way 29 00:01:37,648 --> 00:01:42,313 that we will also account for what happens if there are multiple cells that 30 00:01:42,313 --> 00:01:46,978 are tied to the lowest value, which is something that will happen often, 31 00:01:46,978 --> 00:01:51,770 because we will actually be evaluating cells that has discrete numbers. 32 00:01:51,770 --> 00:01:54,722 Some of them will have eight, four, two options. 33 00:01:54,722 --> 00:01:59,202 And it's likely that we're going to have many cells that are tied for 34 00:01:59,202 --> 00:02:00,628 the lowest number. 35 00:02:00,628 --> 00:02:04,299 So we're going to collect those in a list, and it's going to refer to the cells that 36 00:02:04,299 --> 00:02:07,264 have the lowest entropy, and they could be multiple, right? 37 00:02:08,404 --> 00:02:11,268 The algorithm will pick one random, one of those. 38 00:02:11,268 --> 00:02:12,596 It doesn't really matter which one. 39 00:02:12,596 --> 00:02:15,284 At this point, we just need to choose one. 40 00:02:15,284 --> 00:02:20,084 But we need to account for the algorithm to know that there's in fact many 41 00:02:20,084 --> 00:02:23,004 cells that are tied for the lowest value. 42 00:02:23,004 --> 00:02:25,604 So we're going to continue where we left off. 43 00:02:25,604 --> 00:02:30,183 We are working within, this is our grid script, which we are calling environment, 44 00:02:30,183 --> 00:02:31,224 and tile, right. 45 00:02:32,564 --> 00:02:35,884 Basically the same thing that we have so far. 46 00:02:35,884 --> 00:02:38,764 Let's look into the grid at this point. 47 00:02:38,764 --> 00:02:41,904 I would like to write a few functions that are going to be, 48 00:02:41,904 --> 00:02:43,940 let's just comment them out here. 49 00:02:43,940 --> 00:02:52,204 First, I would like to write the find lowest entropy. 50 00:02:52,204 --> 00:02:58,292 And I would also like to display the lowest entropy. 51 00:02:58,292 --> 00:03:01,724 Just as the graphics that we're showing in some of the slides, 52 00:03:01,724 --> 00:03:05,803 it would be nice to have a very clear representation of which is the tile that 53 00:03:05,803 --> 00:03:07,454 is being evaluated, right? 54 00:03:07,454 --> 00:03:11,744 So we're going to do a little highlight that would display the next value. 55 00:03:11,744 --> 00:03:15,020 So those functions, we're going to write them here, 56 00:03:15,020 --> 00:03:17,920 I'm writing them as kind of comments so far. 57 00:03:17,920 --> 00:03:20,257 So we're going to write those functions first and 58 00:03:20,257 --> 00:03:24,044 then we're going to basically come back and activate them in the run, right? 59 00:03:24,044 --> 00:03:26,644 So let's just write one of them here. 60 00:03:26,644 --> 00:03:32,584 So let's define, let's give ourselves a little bit of space to work here. 61 00:03:33,844 --> 00:03:39,604 So let's call this find lowest entropy. 62 00:03:39,604 --> 00:03:43,644 And we are just going to, for lowest entropy cell. 63 00:03:43,644 --> 00:03:46,064 We're looking for a cell, right? 64 00:03:47,724 --> 00:03:49,204 Self, right. 65 00:03:49,204 --> 00:03:52,004 And usually what we do with the kind of closest point or 66 00:03:52,004 --> 00:03:55,612 smaller distance calculation, we start with a very high number. 67 00:03:55,612 --> 00:04:00,392 So we do lowest entropy would be something like, 68 00:04:00,392 --> 00:04:04,244 something quite large, right. 69 00:04:04,244 --> 00:04:08,572 And then we're going to say cell_x and cell_y, 70 00:04:08,572 --> 00:04:14,239 because we're looking at the x index and the y index of that cell, 71 00:04:14,239 --> 00:04:17,962 we're going to to say none and none, right? 72 00:04:17,962 --> 00:04:21,915 So this is a way of describing two variables in one line. 73 00:04:21,915 --> 00:04:23,843 And we're also going to start a list here, 74 00:04:23,843 --> 00:04:26,724 which is something that we haven't done before. 75 00:04:26,724 --> 00:04:31,564 Several lowest, it's going to be an empty list. 76 00:04:31,564 --> 00:04:35,548 So now we loop through all these cells in the system. 77 00:04:35,548 --> 00:04:43,768 So for x in range(self.columns) and 78 00:04:43,768 --> 00:04:49,996 for y in range(self.rows) 79 00:04:49,996 --> 00:04:58,224 let's calculate the entropy here. 80 00:04:58,224 --> 00:04:59,959 The entropy is the length, 81 00:04:59,959 --> 00:05:03,840 remember that the entropy is the number of possibilities. 82 00:05:03,840 --> 00:05:10,700 So we're going to check the cell x and y. 83 00:05:10,700 --> 00:05:16,252 Cells x and y, right? 84 00:05:16,252 --> 00:05:18,595 And the length of that list, right, 85 00:05:18,595 --> 00:05:22,900 because we know that each cell refers to a list of possible states. 86 00:05:22,900 --> 00:05:26,316 In a way the length of that in this case would be probably four. 87 00:05:26,316 --> 00:05:28,284 That would be the entropy, right? 88 00:05:28,284 --> 00:05:32,215 So now we can say, well, 89 00:05:32,215 --> 00:05:36,523 if it's bigger than one and 90 00:05:36,523 --> 00:05:43,406 smaller than the lowest entropy, right. 91 00:05:43,406 --> 00:05:47,453 So we're doing inline checking that it's in fact bigger than one, 92 00:05:47,453 --> 00:05:49,950 which is the collapsed state, right? 93 00:05:49,950 --> 00:05:53,574 And smaller than the lowest entropy, which is a very high number. 94 00:05:53,574 --> 00:05:57,694 We can agree that we're going to update. 95 00:05:57,694 --> 00:06:05,663 We will, we're going to reset the list. 96 00:06:09,498 --> 00:06:13,140 When I reset the list, 97 00:06:13,140 --> 00:06:18,645 the lowest entropy, It's going to become, 98 00:06:22,908 --> 00:06:27,708 The entropy, right? 99 00:06:27,708 --> 00:06:33,954 We're basically saying if we're below the lowest entropy, let's just assign. 100 00:06:33,954 --> 00:06:36,014 I did that twice, sorry. 101 00:06:36,014 --> 00:06:39,523 Lowest entropy = entropy, right? 102 00:06:39,523 --> 00:06:43,768 We're assigning the lowest entropy to be the current entropy that we're looping 103 00:06:43,768 --> 00:06:44,326 through. 104 00:06:44,326 --> 00:06:53,819 And the index of x and y, It's going to become x and y, right? 105 00:06:53,819 --> 00:06:55,314 From the loop, right? 106 00:06:57,694 --> 00:07:04,085 And the several lowest.append, 107 00:07:04,085 --> 00:07:10,480 we're going to pass on a tuple, x,y 108 00:07:13,206 --> 00:07:18,334 The several lowest is going to contain a tuple of the x and y index, right? 109 00:07:18,334 --> 00:07:19,678 Let me correct a little bit. 110 00:07:19,678 --> 00:07:23,603 I've been writing a little bit fast here, so 111 00:07:23,603 --> 00:07:27,437 I'm going to correct my spelling, several. 112 00:07:29,277 --> 00:07:32,676 And I think here, let me see if there's another one. 113 00:07:32,676 --> 00:07:37,564 Several, I think that's fine, right? 114 00:07:37,564 --> 00:07:42,861 This is the case in which the entropy is in fact smaller than the lowest entropy, 115 00:07:42,861 --> 00:07:44,324 right? 116 00:07:44,324 --> 00:07:48,968 We want to write a second statement that is going to be if it's tied, right? 117 00:07:48,968 --> 00:07:51,400 I'm going to explain this line, which I didn't explain too much. 118 00:07:51,400 --> 00:07:56,080 Why are we resetting the several lowest list, right? 119 00:07:56,080 --> 00:08:00,601 We're going to do a second statement, which is the elif statement here Here, 120 00:08:00,601 --> 00:08:05,212 which is what happens if the entropy is equal to 121 00:08:05,212 --> 00:08:10,708 the lowest_entropy, Right? 122 00:08:10,708 --> 00:08:14,081 This is the case in which we found the lowest_entropy. 123 00:08:14,081 --> 00:08:18,897 Let's say the lowest_entropy initially was 10,000 and then we reduce it to 8, right, 124 00:08:18,897 --> 00:08:22,281 and now we're finding more than one cell that has that number 8. 125 00:08:22,281 --> 00:08:25,421 So if our entropy is equal to the lowest_entropy, 126 00:08:25,421 --> 00:08:29,825 all right, so we have a second cell that matches that lowest number. 127 00:08:29,825 --> 00:08:34,914 Well, at that point, we want to store that value because any time 128 00:08:34,914 --> 00:08:40,002 that we encounter more than one entity with that lowest entropy, 129 00:08:40,002 --> 00:08:45,205 we're going to be storing it in this several_lowest list, right? 130 00:08:48,825 --> 00:08:50,040 There we go, right? 131 00:08:50,040 --> 00:08:52,450 So we append to this list. 132 00:08:52,450 --> 00:08:58,112 If we, in fact, let's say we're collecting all the entropies number 8, 133 00:08:58,112 --> 00:09:00,935 but we suddenly find a number 4. 134 00:09:00,935 --> 00:09:05,150 Well, that becomes the new lowest_entropy, and we reset the list, right? 135 00:09:05,150 --> 00:09:08,897 If we had like three or four entries tied to the number 8 and 136 00:09:08,897 --> 00:09:12,033 that list already contained a few elements, but 137 00:09:12,033 --> 00:09:16,314 then we find the number four, we want to reset the list, right, and 138 00:09:16,314 --> 00:09:21,135 start storing new entities in this new created list, right? 139 00:09:21,135 --> 00:09:25,463 So in this way, the several_lowest will always contain 140 00:09:25,463 --> 00:09:30,060 the most updated lowest and it will only contain either one or 141 00:09:30,060 --> 00:09:34,825 more entries that are tied to that lowest value, right? 142 00:09:34,825 --> 00:09:37,081 So there we have it. 143 00:09:37,081 --> 00:09:40,345 We've looped through the grid. 144 00:09:40,345 --> 00:09:46,642 So let's just find, now let's check if the length of this, 145 00:09:46,642 --> 00:09:49,841 whoops, several_lowest. 146 00:09:49,841 --> 00:09:54,805 So this list, so we can check, is this bigger than 1? 147 00:09:58,945 --> 00:10:03,385 And if it's bigger than 1, it means that we have several tied lowest. 148 00:10:03,385 --> 00:10:08,461 And we could say that the cell, let's pick 149 00:10:08,461 --> 00:10:13,713 a random choice from the several_lowest. 150 00:10:13,713 --> 00:10:18,665 So pick one of them is what we spoke about before. 151 00:10:19,845 --> 00:10:22,620 And here what we're going to be updating with this function, 152 00:10:22,620 --> 00:10:24,701 which is finding the lowest_entropy. 153 00:10:24,701 --> 00:10:30,104 If you remember, we created all the way to the top of the script these two entries, 154 00:10:30,104 --> 00:10:34,904 which is the next cell, and we use those to start the algorithm, right? 155 00:10:34,904 --> 00:10:38,362 We started them here, we say the next cell, 156 00:10:38,362 --> 00:10:41,829 it's going to be based on this information. 157 00:10:41,829 --> 00:10:44,710 So what we're going to be doing all the way down here, 158 00:10:44,710 --> 00:10:47,256 we're going to be updating this next cell, and 159 00:10:47,256 --> 00:10:51,615 we're not going to be using this kind of arbitrary numbers that we used before. 160 00:10:52,635 --> 00:11:00,268 We're going to be using the cells or, sorry, 161 00:11:00,268 --> 00:11:06,675 the selected cell from this random. 162 00:11:06,675 --> 00:11:12,509 The first entry of that is the index, the x, right, 163 00:11:12,509 --> 00:11:19,555 because we're looping through the tuple of indices, right? 164 00:11:20,935 --> 00:11:23,675 The 0 and the 1, right? 165 00:11:23,675 --> 00:11:30,812 And then return a cell[0] and 166 00:11:30,812 --> 00:11:36,097 cell[1], else, so 167 00:11:36,097 --> 00:11:42,175 this is the case if there's 168 00:11:42,175 --> 00:11:47,389 more than 1, right? 169 00:11:47,389 --> 00:11:53,114 But if it's only 1, we can just do something slightly, 170 00:11:53,114 --> 00:11:58,573 it's kind of similar than this exit or this return. 171 00:11:58,573 --> 00:12:01,045 Just write it here and then do some changes. 172 00:12:01,045 --> 00:12:07,164 So the next cell would be a cell_x, 173 00:12:11,391 --> 00:12:12,415 cell_y. 174 00:12:16,195 --> 00:12:18,735 And you might be wondering what are these values? 175 00:12:19,835 --> 00:12:21,115 Where are we getting these from? 176 00:12:21,115 --> 00:12:23,175 Let's just double-check that in a minute. 177 00:12:24,435 --> 00:12:26,931 So these have been declared at the very beginning of this function, right? 178 00:12:26,931 --> 00:12:27,835 So if we go here, 179 00:12:27,835 --> 00:12:32,207 these values all the way at the beginning of the function were defined as none. 180 00:12:32,207 --> 00:12:36,455 But as we loop through the list, we assign those, right? 181 00:12:36,455 --> 00:12:38,842 If we only find one entropy cell, 182 00:12:38,842 --> 00:12:44,447 those are already assigned to the tuple x and y, sorry, to the x and y index. 183 00:12:44,447 --> 00:12:46,115 So we can use those straight away. 184 00:12:47,855 --> 00:12:50,519 So that's the function of finding the lowest_entropy. 185 00:12:50,519 --> 00:12:55,315 We mostly use it to update the next cell value, right? 186 00:12:56,625 --> 00:12:59,505 So we start with an arbitrary number that is 15 and 7. 187 00:12:59,505 --> 00:13:04,945 And as we loop through the algorithm, we find the lowest entropy point. 188 00:13:04,945 --> 00:13:08,005 So let's just call this algorithm because this is not currently called. 189 00:13:08,005 --> 00:13:16,229 So here we could say self.lowest_entropy, 190 00:13:19,462 --> 00:13:20,725 Like that, right? 191 00:13:22,455 --> 00:13:25,543 And at this point, if this runs, we could have a loop. 192 00:13:25,543 --> 00:13:28,764 We're going to see that there's some errors and there's some kind of exceptions 193 00:13:28,764 --> 00:13:31,623 that we might run into, but let's see what we have at this moment. 194 00:13:31,623 --> 00:13:37,335 So we run the algorithm and it starts looping and it crashes. 195 00:13:37,335 --> 00:13:38,591 That's totally fine. 196 00:13:38,591 --> 00:13:39,765 Let's understand what's going on. 197 00:13:39,765 --> 00:13:45,337 So the algorithm will kind of gradually go from cell to cell, each frame, right? 198 00:13:45,337 --> 00:13:46,228 Each frame, 199 00:13:46,228 --> 00:13:51,414 it's going to collapse a cell within this kind of wave_function_collapse, 200 00:13:51,414 --> 00:13:55,707 propagate a search, update the entropy of the neighbors, and 201 00:13:55,707 --> 00:14:00,905 then move down the line to the find_lowest_entropy and then start over. 202 00:14:00,905 --> 00:14:03,433 And it's going to repeat this sequence over and over and over. 203 00:14:03,433 --> 00:14:08,695 The problem is because we have a system that has only four tiles, 204 00:14:08,695 --> 00:14:13,958 it is possible that the algorithm doesn't run into a solution, 205 00:14:13,958 --> 00:14:17,285 that it kind of runs into errors, right? 206 00:14:17,285 --> 00:14:21,932 So we're going to expand these tiles to all the possible states that this 207 00:14:21,932 --> 00:14:23,743 system can actually have so 208 00:14:23,743 --> 00:14:28,245 that we in fact find a solution to the whole configuration, right? 209 00:14:29,865 --> 00:14:31,297 But we're going to do that in the next video. 210 00:14:31,297 --> 00:14:35,161 Let's first conclude by writing this display entropy. 211 00:14:35,161 --> 00:14:38,706 I would like to have a highlight of which is 212 00:14:38,706 --> 00:14:43,077 the cell that is being evaluated at a time, right? 213 00:14:43,077 --> 00:14:48,548 So let's just do a simple visualization for that, right? 214 00:14:48,548 --> 00:14:51,177 So I'm going to call it display lowest entropy. 215 00:14:51,177 --> 00:14:52,872 I'm going to write it all the way to the bottom. 216 00:14:52,872 --> 00:14:56,701 So we have display_grid somewhere here, but 217 00:14:56,701 --> 00:15:01,316 we're starting to operate within the display_grid, 218 00:15:01,316 --> 00:15:06,928 here we can use a function to display the lowest_entropy, right? 219 00:15:06,928 --> 00:15:07,771 So display, 220 00:15:11,503 --> 00:15:18,725 display_lowest_entropy(self, x, y), right? 221 00:15:18,725 --> 00:15:23,220 So what we're going to do is that we're going to pass an x and 222 00:15:23,220 --> 00:15:28,277 y coordinate for that cell, and let's do some exceptions. 223 00:15:28,277 --> 00:15:32,634 We're making sure that if x is not None, 224 00:15:32,634 --> 00:15:39,299 it might happen that at some point the algorithm concludes and 225 00:15:39,299 --> 00:15:46,365 we reach a point where we cannot run this visualization anymore. 226 00:15:48,425 --> 00:15:51,721 So I like having some measures. 227 00:15:51,721 --> 00:15:57,728 So the tile size could be calculated by a float number, 228 00:15:57,728 --> 00:16:04,071 which is the self, .world x divided 229 00:16:04,071 --> 00:16:09,678 by the columns, right? 230 00:16:09,678 --> 00:16:14,149 And then let's just 231 00:16:14,149 --> 00:16:18,621 define the stroke. 232 00:16:18,621 --> 00:16:25,661 I'm going to do a red color with noFill just to make it a highlight. 233 00:16:25,661 --> 00:16:32,267 And a strokeweight of 3 or, sorry, 3, r? 234 00:16:32,267 --> 00:16:33,606 I think that should be enough. 235 00:16:33,606 --> 00:16:34,754 And then we pushMatrix. 236 00:16:39,721 --> 00:16:47,977 We translate in x times the tile size, right? 237 00:16:47,977 --> 00:16:53,822 Again, we're drawing a rectangle on top of and 238 00:16:53,822 --> 00:16:56,607 y times the tile size. 239 00:16:58,912 --> 00:17:04,564 Let's define the rectangle rectMode to be CORNER. 240 00:17:04,564 --> 00:17:09,628 And let's draw that rectangle at 0, 241 00:17:09,628 --> 00:17:14,539 0, tile size, tile size, right? 242 00:17:14,539 --> 00:17:17,397 Because we're using it to translate the coordinate we can use 0, 243 00:17:17,397 --> 00:17:20,061 0 because we're using push and push and pop matrix, right? 244 00:17:20,061 --> 00:17:24,346 And now we pop the matrix. 245 00:17:24,346 --> 00:17:26,285 If you like this to be shorter, 246 00:17:26,285 --> 00:17:30,913 you can actually type the coordinates of the position of the rectangle and 247 00:17:30,913 --> 00:17:34,136 avoid the whole kind of push popMatrix situation. 248 00:17:34,136 --> 00:17:37,785 But this would allow you to expand on that visualization if you want, right? 249 00:17:37,785 --> 00:17:40,290 And then we go back I would like to kind of, 250 00:17:40,290 --> 00:17:45,235 whenever I change the strokeweight, I like to return the strokeweight because 251 00:17:45,235 --> 00:17:49,764 we hadn't been manipulating the strokeweight anywhere else, right? 252 00:17:49,764 --> 00:17:51,291 So if I kind of change it to 3, 253 00:17:51,291 --> 00:17:54,617 I don't want the whole drawing to become strokeweight of 3. 254 00:17:54,617 --> 00:17:56,735 I'm going to return it to 1, right? 255 00:17:56,735 --> 00:18:01,799 So we have this function that would draw the lowest entropy. 256 00:18:01,799 --> 00:18:07,096 Let's see if this has any errors or it's working. 257 00:18:07,096 --> 00:18:09,646 So let's just see here. 258 00:18:09,646 --> 00:18:16,904 So we're going to use self.display lowest entropy, right? 259 00:18:19,157 --> 00:18:22,053 And we have to provide some arguments, right? 260 00:18:22,053 --> 00:18:25,081 We have to provide the x and the y, right? 261 00:18:25,081 --> 00:18:30,316 And what is the x and the y for this highlight? 262 00:18:30,316 --> 00:18:33,373 Well, we can use these global values, 263 00:18:33,373 --> 00:18:38,015 these values that we have for the next cell x and next cell y. 264 00:18:38,015 --> 00:18:43,098 This is going to be at all times the cell that would be evaluated next, right? 265 00:18:43,098 --> 00:18:48,823 So let's see if this visualization now, it's actually showing us. 266 00:18:48,823 --> 00:18:53,151 Well, we're running into the same problem of crashing at some point due to 267 00:18:53,151 --> 00:18:54,879 the possibilities, right? 268 00:18:54,879 --> 00:18:56,582 But we do have a highlight, right? 269 00:18:56,582 --> 00:18:58,784 So let's just run that a couple of times. 270 00:18:58,784 --> 00:19:06,274 Because of the randomness, it might be that we run it a few more iterations. 271 00:19:07,828 --> 00:19:12,415 You see, like different times, we run it more or less, but we often will find 272 00:19:12,415 --> 00:19:17,146 ourselves in a position of not finding a solution to continuing the algorithm, 273 00:19:17,146 --> 00:19:17,657 right? 274 00:19:17,657 --> 00:19:20,507 So we're going to have to provide more tile options for 275 00:19:20,507 --> 00:19:23,176 the algorithm to really resolve this equation. 276 00:19:23,176 --> 00:19:25,590 If you run this algorithm at this point, 277 00:19:25,590 --> 00:19:29,286 you see that it runs pretty quickly until it crashes, right? 278 00:19:29,286 --> 00:19:33,781 One of the things that I like doing is trying to slow down 279 00:19:33,781 --> 00:19:38,863 the algorithm to the point in which we could actually click and 280 00:19:38,863 --> 00:19:42,302 execute a loop or kind of a frame, right? 281 00:19:42,302 --> 00:19:45,721 I would like to implement that now. 282 00:19:45,721 --> 00:19:49,431 It's actually a really simple technique, but 283 00:19:49,431 --> 00:19:52,685 it allows us to have some kind of control. 284 00:19:52,685 --> 00:20:00,713 So in the draw, let's just create a global count and 285 00:20:00,713 --> 00:20:05,455 a t count and we're going to say if 286 00:20:05,455 --> 00:20:11,292 the count is smaller than the t count, 287 00:20:11,292 --> 00:20:15,123 I'm going to write this and 288 00:20:15,123 --> 00:20:20,798 explain what I'm doing in a minute. 289 00:20:20,798 --> 00:20:25,331 We are going to run the environment, right? 290 00:20:25,331 --> 00:20:27,914 So this is the loop that is happening, right? 291 00:20:27,914 --> 00:20:34,763 Let's comment out this background for a moment, right? 292 00:20:34,763 --> 00:20:40,835 And, If we press a key, 293 00:20:40,835 --> 00:20:45,333 let's just create a bit of space here. 294 00:20:48,425 --> 00:20:51,545 Let's use keyReleased. 295 00:20:51,545 --> 00:20:57,596 So if we release a key we advance the t count. 296 00:20:57,596 --> 00:20:58,188 So, 297 00:21:09,824 --> 00:21:12,932 So what we're saying here is that let's just use the keyboard. 298 00:21:12,932 --> 00:21:19,175 So the algorithm by itself, it's not going to start, right? 299 00:21:19,175 --> 00:21:25,015 Actually, let's just start these values here. 300 00:21:25,015 --> 00:21:32,188 count=0 and t count=0, right? 301 00:21:32,188 --> 00:21:33,889 So let's understand what we're doing here. 302 00:21:33,889 --> 00:21:37,978 We're saying we're starting both at 0, right? 303 00:21:37,978 --> 00:21:43,050 If we press the key, we advance the t count so 304 00:21:43,050 --> 00:21:46,073 that will go from 0 to 1. 305 00:21:46,073 --> 00:21:49,772 At that point this algorithm will run and execute, right? 306 00:21:49,772 --> 00:21:51,360 Or will start executing. 307 00:21:51,360 --> 00:21:56,568 What we want at this point is also make sure that after we execute one loop, 308 00:21:56,568 --> 00:21:58,674 we say count +=1, right? 309 00:21:58,674 --> 00:22:01,620 So at this point the count will match the t count. 310 00:22:01,620 --> 00:22:04,308 So every time we press a key, 311 00:22:04,308 --> 00:22:09,802 we give it an extra possible step to move forward, right? 312 00:22:09,802 --> 00:22:13,377 And in such a way we will actually be able to control with our keys, 313 00:22:13,377 --> 00:22:17,667 with the keyboard or you can use the mouse or anything else changing a little bit 314 00:22:17,667 --> 00:22:21,849 the function to control how the flow of the algorithm is executing, right? 315 00:22:21,849 --> 00:22:26,169 So you'll see that nothing happens, but if we press once, you'll see, 316 00:22:26,169 --> 00:22:30,560 we collapse the cell and we find the lowest entropy point, we press again, 317 00:22:30,560 --> 00:22:35,185 we collapse the cell and we find the lowest entropy point and so forth, right? 318 00:22:35,185 --> 00:22:41,225 So we could actually kind of start looping through until we crash it, right? 319 00:22:41,225 --> 00:22:46,170 So this is a way of like slowing down the execution of the algorithm and 320 00:22:46,170 --> 00:22:50,612 allows us to debug a little bit more clearly what's going on. 321 00:22:50,612 --> 00:22:54,905 So we're going to leave it here and I'll see you in the next video where we're 322 00:22:54,905 --> 00:22:58,880 going to kind of continue expanding and adding more tiles to the system. 323 00:22:58,880 --> 00:22:59,636 We'll see you then.