perfetto-ui: Tickmark panel

UI to display where search results exist across a time range.

Bug:111169965
Change-Id: I7063a7563f4c3b4487c1b2d348ded516b7f10461

ui/src/frontend/tickmark_panel.ts

diff --git a/ui/src/frontend/tickmark_panel.ts b/ui/src/frontend/tickmark_panel.ts
new file mode 100644
index 0000000..81a4362
--- /dev/null
+++ b/ui/src/frontend/tickmark_panel.ts
@@ -0,0 +1,65 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use size file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as m from 'mithril';
+
+import {SearchSummary} from '../common/search_data';
+import {globals} from './globals';
+import {gridlines} from './gridline_helper';
+
+import {Panel, PanelSize} from './panel';
+import {TRACK_SHELL_WIDTH} from './track_constants';
+
+// This is used to display the summary of search results.
+export class TickmarkPanel extends Panel {
+  // TODO(taylori): Replace this with real data.
+  private all: number[] = [...Array.from<number>({length: 100}).keys()];
+  private data: SearchSummary = {
+    tsStarts: new Float64Array(this.all.filter(i => i % 2 === 0)),
+    tsEnds: new Float64Array(this.all.filter(i => i % 2 === 1)),
+    count: new Uint8Array(
+        Array.from({length: 50}, () => Math.floor(Math.random() * 10))),
+  };
+
+  view() {
+    return m('.tickbar');
+  }
+
+  renderCanvas(ctx: CanvasRenderingContext2D, size: PanelSize) {
+    const {timeScale, visibleWindowTime} = globals.frontendLocalState;
+
+    ctx.fillStyle = '#999';
+    for (const xAndTime of gridlines(
+             size.width, visibleWindowTime, timeScale)) {
+      ctx.fillRect(xAndTime[0], 0, 1, size.height);
+    }
+
+    const data = this.data;
+    const maxCount = Math.max(...data.count);
+    const colorInterval = 40 / maxCount;
+    for (let i = 0; i < data.tsStarts.length; i++) {
+      const tStart = data.tsStarts[i];
+      const tEnd = data.tsEnds[i];
+      const count = data.count[i];
+      if (tEnd <= visibleWindowTime.start || tStart >= visibleWindowTime.end) {
+        continue;
+      }
+      const rectStart = timeScale.timeToPx(tStart) + TRACK_SHELL_WIDTH;
+      const rectEnd = timeScale.timeToPx(tEnd) + TRACK_SHELL_WIDTH;
+      ctx.fillStyle =
+          `hsl(59, 100%, ${50 + (Math.round(colorInterval * count))}%)`;
+      ctx.fillRect(rectStart, 0, rectEnd - rectStart, size.height);
+    }
+  }
+}