From dde8f172dc50952f0585fcdcca212821d4c57f1f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rn-Michael=20Miehe?= <jmm@yavook.de>
Date: Mon, 23 Jan 2023 22:33:39 +0000
Subject: [PATCH] coordinate transformation into ThouCanvas

---
 ui/src/components/rects/RectPad.vue    | 46 ++++++-----------
 ui/src/components/rects/ThouCanvas.vue | 70 ++++++++++++++++++++++++++
 2 files changed, 84 insertions(+), 32 deletions(-)
 create mode 100644 ui/src/components/rects/ThouCanvas.vue

diff --git a/ui/src/components/rects/RectPad.vue b/ui/src/components/rects/RectPad.vue
index 281c9a6..e84cc5d 100644
--- a/ui/src/components/rects/RectPad.vue
+++ b/ui/src/components/rects/RectPad.vue
@@ -1,11 +1,7 @@
 <template>
-  <svg
-    xmlns="http://www.w3.org/2000/svg"
-    viewBox="0 0 1000 1000"
-    preserveAspectRatio="none"
+  <ThouCanvas
     @mousedown.left="draw_start"
     @mouseup.left="draw_finish"
-    @contextmenu.prevent
     @mousedown.right="drag_start"
     @mouseup.right="drag_finish"
     @mousemove="on_mousemove"
@@ -22,29 +18,18 @@
       :focused="true"
       :rectangle="preview_rectangle"
     />
-  </svg>
+  </ThouCanvas>
 </template>
 
 <script lang="ts">
 import { Vue, Options } from "vue-class-component";
 import { Vector2D, Rectangle } from "./rectangles";
+import ThouCanvas from "./ThouCanvas.vue";
 import Rect from "./Rect.vue";
 
-function get_event_thous(event: MouseEvent): Vector2D {
-  if (event.currentTarget === null) {
-    return new Vector2D();
-  }
-
-  const target = event.currentTarget as Element;
-
-  return new Vector2D(
-    Math.round((event.offsetX / target.clientWidth) * 1000),
-    Math.round((event.offsetY / target.clientHeight) * 1000)
-  );
-}
-
 @Options({
   components: {
+    ThouCanvas,
     Rect,
   },
 })
@@ -76,14 +61,14 @@ export default class RectPad extends Vue {
     return this.rectangles.splice(idx, 1)[0];
   }
 
-  private draw_start(event: MouseEvent) {
+  private draw_start(event: MouseEvent, point: Vector2D) {
     if (this.preview_visible) {
       return;
     }
 
     this.drawing = true;
-    this.preview_corner1 = get_event_thous(event);
-    this.preview_corner2 = get_event_thous(event);
+    this.preview_corner1 = point;
+    this.preview_corner2 = point;
   }
 
   private draw_finish() {
@@ -100,12 +85,11 @@ export default class RectPad extends Vue {
     this.rectangles.push(this.preview_rectangle);
   }
 
-  private drag_start(event: MouseEvent) {
+  private drag_start(event: MouseEvent, point: Vector2D) {
     if (this.preview_visible) {
       return;
     }
 
-    const point = get_event_thous(event);
     this.drag_rect = this.pop_rectangle(point);
 
     if (this.drag_rect === undefined) {
@@ -128,31 +112,29 @@ export default class RectPad extends Vue {
     this.rectangles.push(this.preview_rectangle);
   }
 
-  private on_mousemove(event: MouseEvent) {
+  private on_mousemove(event: MouseEvent, point: Vector2D) {
     if (this.drawing) {
-      this.preview_corner2 = get_event_thous(event);
+      this.preview_corner2 = point;
     } else if (this.dragging && this.drag_rect) {
-      const movement = get_event_thous(event).minus(this.drag_origin);
+      const movement = point.minus(this.drag_origin);
 
       this.preview_corner1 = this.drag_rect.origin.plus(movement);
       this.preview_corner2 = this.drag_rect.corner.plus(movement);
     }
   }
 
-  private remove_rect(event: MouseEvent) {
+  private remove_rect(event: MouseEvent, point: Vector2D) {
     if (this.preview_visible) {
       return;
     }
 
-    this.pop_rectangle(get_event_thous(event));
+    this.pop_rectangle(point);
   }
 }
 </script>
 
 <style scoped>
-svg {
+* {
   cursor: crosshair;
-  height: 100%;
-  width: 100%;
 }
 </style>
\ No newline at end of file
diff --git a/ui/src/components/rects/ThouCanvas.vue b/ui/src/components/rects/ThouCanvas.vue
new file mode 100644
index 0000000..8c471a0
--- /dev/null
+++ b/ui/src/components/rects/ThouCanvas.vue
@@ -0,0 +1,70 @@
+<template>
+  <svg
+    xmlns="http://www.w3.org/2000/svg"
+    viewBox="0 0 1000 1000"
+    preserveAspectRatio="none"
+    @contextmenu.prevent
+    @mousedown="transform_mouse_event"
+    @mousemove="transform_mouse_event"
+    @mouseup="transform_mouse_event"
+    @click="transform_mouse_event"
+    @dblclick="transform_mouse_event"
+  >
+    <slot name="default" />
+  </svg>
+</template>
+
+<script lang="ts">
+import { Vue, Options } from "vue-class-component";
+import { Vector2D } from "./rectangles";
+
+function get_event_thous(event: MouseEvent): Vector2D {
+  if (event.currentTarget === null) {
+    return new Vector2D();
+  }
+
+  const target = event.currentTarget as Element;
+
+  return new Vector2D(
+    Math.round((event.offsetX / target.clientWidth) * 1000),
+    Math.round((event.offsetY / target.clientHeight) * 1000)
+  );
+}
+
+function mouse_event_validator(event: object, point: object): boolean {
+  if (!(event instanceof MouseEvent)) {
+    console.warn(event, "is not a MouseEvent!");
+    return false;
+  }
+
+  if (!(point instanceof Vector2D)) {
+    console.warn(point, "is not a Vector2D!");
+    return false;
+  }
+
+  return true;
+}
+
+@Options({
+  emits: {
+    mousedown: mouse_event_validator,
+    mouseup: mouse_event_validator,
+    mousemove: mouse_event_validator,
+    click: mouse_event_validator,
+    dblclick: mouse_event_validator,
+  },
+})
+export default class ThouCanvas extends Vue {
+  private transform_mouse_event(event: MouseEvent) {
+    const point = get_event_thous(event);
+    this.$emit(event.type, event, point);
+  }
+}
+</script>
+
+<style scoped>
+svg {
+  height: 100%;
+  width: 100%;
+}
+</style>
\ No newline at end of file