[refactor] collect stuff into new mod paint

emigui/src/introspection.rs

@@ -0,0 +1,63 @@
+//! uis for emigui types.
+use crate::{
+    containers::show_tooltip,
+    label,
+    math::*,
+    paint::{color::WHITE, PaintCmd, Texture, Triangles, Vertex},
+};
+
+impl Texture {
+    pub fn ui(&self, ui: &mut crate::Ui) {
+        ui.add(label!(
+            "Texture size: {} x {} (hover to zoom)",
+            self.width,
+            self.height
+        ));
+        let mut size = vec2(self.width as f32, self.height as f32);
+        if size.x > ui.available().width() {
+            size *= ui.available().width() / size.x;
+        }
+        let interact = ui.reserve_space(size, None);
+        let rect = interact.rect;
+        let top_left = Vertex {
+            pos: rect.min,
+            uv: (0, 0),
+            color: WHITE,
+        };
+        let bottom_right = Vertex {
+            pos: rect.max,
+            uv: (self.width as u16 - 1, self.height as u16 - 1),
+            color: WHITE,
+        };
+        let mut triangles = Triangles::default();
+        triangles.add_rect(top_left, bottom_right);
+        ui.add_paint_cmd(PaintCmd::Triangles(triangles));
+
+        if interact.hovered {
+            show_tooltip(ui.ctx(), |ui| {
+                let pos = ui.top_left();
+                let zoom_rect = ui.reserve_space(vec2(128.0, 128.0), None).rect;
+                let u = remap_clamp(pos.x, rect.range_x(), 0.0..=self.width as f32 - 1.0).round();
+                let v = remap_clamp(pos.y, rect.range_y(), 0.0..=self.height as f32 - 1.0).round();
+
+                let texel_radius = 32.0;
+                let u = clamp(u, texel_radius..=self.width as f32 - 1.0 - texel_radius);
+                let v = clamp(v, texel_radius..=self.height as f32 - 1.0 - texel_radius);
+
+                let top_left = Vertex {
+                    pos: zoom_rect.min,
+                    uv: ((u - texel_radius) as u16, (v - texel_radius) as u16),
+                    color: WHITE,
+                };
+                let bottom_right = Vertex {
+                    pos: zoom_rect.max,
+                    uv: ((u + texel_radius) as u16, (v + texel_radius) as u16),
+                    color: WHITE,
+                };
+                let mut triangles = Triangles::default();
+                triangles.add_rect(top_left, bottom_right);
+                ui.add_paint_cmd(PaintCmd::Triangles(triangles));
+            });
+        }
+    }
+}