34 lines
807 B
JavaScript
34 lines
807 B
JavaScript
// chart.js
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export function drawChart(canvas, history) {
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if (!canvas || !history?.length) return;
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const rect = canvas.getBoundingClientRect();
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const displayHeight = rect.height || 120;
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const displayWidth = rect.width || 800;
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canvas.width = displayWidth;
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canvas.height = displayHeight;
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const ctx = canvas.getContext("2d");
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const w = canvas.width;
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const h = canvas.height;
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ctx.clearRect(0, 0, w, h);
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const stepX = w / history.length;
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const scaleY = h / 63;
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ctx.strokeStyle = "#00ff88";
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ctx.lineWidth = 2;
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ctx.beginPath();
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for (let i = 0; i < history.length; i++) {
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const x = i * stepX;
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const y = h - history[i] * scaleY;
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if (i === 0) ctx.moveTo(x, y);
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else ctx.lineTo(x, y);
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}
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ctx.stroke();
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} |