wehub-resource-sync
32 lines
881 B
C
32 lines
881 B
C
#pragma once
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#include "LGFX.h"
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void DrawScanLines(LGFX_Sprite& buf, const int x0, const int y0, const int x1, const int y1, const int thickness, const int trailBrightness, const int spacing)
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{
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float dx = x1 - x0;
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float dy = y1 - y0;
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float len = sqrt(dx * dx + dy * dy);
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// perpendicular unit vector
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float px = -dy / len;
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float py = dx / len;
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for (int i = 0; i <= thickness; i++) {
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// 1.0 at centre, 0.0 at edges
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float t = i / (float)(thickness);
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uint8_t brightness = (uint8_t)(t * trailBrightness);
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buf.drawLine(
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x0, y0,
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x1 + (px * (i * spacing)), y1 + (py * (i * spacing)),
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lgfx::color888(0, brightness, 0)
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);
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}
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buf.drawLine(
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x0, y0,
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x1 + (px * (thickness * spacing)), y1 + (py * (thickness * spacing)),
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lgfx::color888(0, 200, 0)
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);
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} |