text.composite_texture source code

1 module text.composite_texture;
2 
3 import std.conv;
4 import std.range;
5 import std.algorithm;
6 
7 import fluid;
8 
9 @safe:
10 
11 unittest {
12 
13     auto content = vscrollable!label(
14         .nullTheme,
15         "One\nTwo\nThree\nFour\nFive\n"
16     );
17     auto root = testSpace(content);
18 
19     root.draw();
20 
21     // One chunk only
22     assert(content.text.texture.chunks.length == 1);
23 
24     // This one chunk must have been drawn
25     root.drawAndAssert(
26         content.drawsImage(content.text.texture.chunks[0].image).at(0, 0).ofColor("#fff")
27     );
28 
29 }
30 
31 @("Only visible chunks are rendered")
32 unittest {
33 
34     enum chunkSize = CompositeTexture.maxChunkSize;
35 
36     auto content = vscrollable!label(
37         .nullTheme,
38         "One\nTwo\nThree\nFour\nFive\n"
39     );
40     auto root = sizeLock!testSpace(
41         .sizeLimit(800, 600),
42         .cropViewport,
43         content
44     );
45 
46     // Add a lot more text
47     content.text = content.text.repeat(30).joiner.text;
48     root.draw();
49 
50     const textSize = content.text.size;
51 
52     // Make sure assumptions for this test are sound:
53     assert(textSize.y > chunkSize * 2, "Generated text must span at least three chunks");
54     assert(root.limit.y < chunkSize,  "Window size must be smaller than chunk size");
55 
56     // Three chunks, only the first one is drawn and generated
57     assert(content.text.texture.chunks.length >= 3);
58     assert(content.text.texture.chunks[0].isValid);
59     assert(content.text.texture.chunks[1 .. $].all!((ref a) => !a.isValid));
60     root.drawAndAssert(
61         content.drawsImage(content.text.texture.chunks[0].image).at(0, 0).ofColor("#fff"),
62         content.doesNotDraw(),
63     );
64 
65     // Scroll just enough so that both chunks should be on screen
66     // This should cause the second chunk to generate too
67     content.scroll = chunkSize - 1;
68     root.draw();
69     assert(content.text.texture.chunks[0 .. 2].all!((ref a) => a.isValid));
70     assert(content.text.texture.chunks[2 .. $].all!((ref a) => !a.isValid));
71 
72     root.drawAndAssert(
73         content.drawsImage(content.text.texture.chunks[0].image).at(0, -content.scroll).ofColor("#fff"),
74         content.drawsImage(content.text.texture.chunks[1].image).at(0, -content.scroll + chunkSize).ofColor("#fff"),
75         content.doesNotDraw(),
76     ),
77 
78     // Skip to third chunk, force regeneration
79     content.scroll = 2 * chunkSize - 1;
80     root.updateSize();
81     root.draw();
82 
83     // Because of the resize, the first chunk must have been destroyed
84     assert(content.text.texture.chunks[0 .. 1].all!((ref a) => !a.isValid));
85     assert(content.text.texture.chunks[1 .. 3].all!((ref a) => a.isValid));
86     assert(content.text.texture.chunks[3 .. $].all!((ref a) => !a.isValid));
87 
88     root.drawAndAssert(
89         content.drawsImage(content.text.texture.chunks[1].image).at(0, -content.scroll + chunkSize).ofColor("#fff"),
90         content.drawsImage(content.text.texture.chunks[2].image).at(0, -content.scroll + chunkSize*2).ofColor("#fff"),
91         content.doesNotDraw(),
92     );
93 
94 }