From 01386616aad0547e672671bfcd6009c79aed9547 Mon Sep 17 00:00:00 2001
From: Herve Nicol <12008875+hervenicol@users.noreply.github.com>
Date: Sun, 4 Sep 2022 18:11:38 +0200
Subject: [PATCH] menu: faster background drawing using FastHLines
---
menu.go | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 75 insertions(+), 6 deletions(-)
diff --git a/menu.go b/menu.go
index 9289a13..52f81af 100644
--- a/menu.go
+++ b/menu.go
@@ -11,6 +11,75 @@ import (
"tinygo.org/x/tinyfont/proggy"
)
+// FilledTriangle draws a filled triangle given three points
+// Code from tinydraw, but faster and may not work on all displays
+func FilledTriangle(x0 int16, y0 int16, x1 int16, y1 int16, x2 int16, y2 int16, color color.RGBA) {
+ if y0 > y1 {
+ x0, y0, x1, y1 = x1, y1, x0, y0
+ }
+ if y1 > y2 {
+ x1, y1, x2, y2 = x2, y2, x1, y1
+ }
+ if y0 > y1 {
+ x0, y0, x1, y1 = x1, y1, x0, y0
+ }
+
+ if y0 == y2 { // y0 = y1 = y2 : it's a line
+ a := x0
+ b := x0
+ if x1 < a {
+ a = x1
+ } else if x1 > b {
+ b = x1
+ }
+ if x2 < a {
+ a = x2
+ } else if x2 > b {
+ b = x2
+ }
+ // Line(display, a, y0, b, y0, color)
+ display.DrawFastHLine(a, b, y0, color)
+ return
+ }
+
+ dx01 := x1 - x0
+ dy01 := y1 - y0
+ dx02 := x2 - x0
+ dy02 := y2 - y0
+ dx12 := x2 - x1
+ dy12 := y2 - y1
+
+ sa := int16(0)
+ sb := int16(0)
+ a := int16(0)
+ b := int16(0)
+
+ last := y1 - 1
+ if y1 == y2 {
+ last = y1
+ }
+
+ y := y0
+ for ; y <= last; y++ {
+ a = x0 + sa/dy01
+ b = x0 + sb/dy02
+ sa += dx01
+ sb += dx02
+ display.DrawFastHLine(a, b, y, color)
+ }
+
+ sa = dx12 * (y - y1)
+ sb = dx02 * (y - y0)
+
+ for ; y <= y2; y++ {
+ a = x1 + sa/dy12
+ b = x0 + sb/dy02
+ sa += dx12
+ sb += dx02
+ display.DrawFastHLine(a, b, y, color)
+ }
+}
+
func menu() int16 {
display.FillScreen(color.RGBA{0, 0, 0, 255})
options := []string{
@@ -23,12 +92,12 @@ func menu() int16 {
bgColor := color.RGBA{0, 40, 70, 255}
display.FillScreen(bgColor)
- tinydraw.FilledTriangle(&display, 0, 128, 0, 45, 45, 0, color.RGBA{255, 255, 255, 255})
- tinydraw.FilledTriangle(&display, 45, 0, 0, 128, 145, 0, color.RGBA{255, 255, 255, 255})
- tinydraw.FilledTriangle(&display, 0, 128, 15, 128, 145, 0, color.RGBA{255, 255, 255, 255})
- for i := int16(0); i < 8; i++ {
- tinydraw.Line(&display, 0, 110+i, 110+i, 0, bgColor)
- }
+ FilledTriangle(0, 128, 0, 45, 45, 0, color.RGBA{255, 255, 255, 255})
+ FilledTriangle(45, 0, 0, 128, 145, 0, color.RGBA{255, 255, 255, 255})
+ FilledTriangle(0, 128, 15, 128, 145, 0, color.RGBA{255, 255, 255, 255})
+
+ FilledTriangle(0, 110, 110, 0, 117, 0, bgColor)
+ FilledTriangle(0, 110, 0, 117, 117, 0, bgColor)
selected := int16(0)
numOpts := int16(len(options))