From 74aa441111869fecc9b59ce4508e900b62d7f6c0 Mon Sep 17 00:00:00 2001
From: liuyihui <liuyihui02@gmail.com>
Date: Thu, 27 Apr 2023 13:44:11 +0800
Subject: [PATCH] fix: Horizontal and vertical screen switching; feat: DrawLine
 in LCD

---
 include/tftlcd.h |  5 +++--
 src/tftlcd.c     | 45 ++++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/include/tftlcd.h b/include/tftlcd.h
index b417267..ecfd0ce 100644
--- a/include/tftlcd.h
+++ b/include/tftlcd.h
@@ -32,7 +32,7 @@
 typedef unsigned char uchar;
 
 // LCD function 1 enable
-#define USE_HORIZONTAL 0  // 横屏
+#define USE_HORIZONTAL 1  // 横屏
 #define LCD_FAST_IO 1     // 快速IO
 
 // LCD size
@@ -105,12 +105,13 @@ typedef unsigned char uchar;
 
 void LCD_RESET();
 void LCD_Init();
+void LCD_Clear();
 void LCD_SetColor(uint16_t color);
 void LCD_SetBackColor(uint16_t color);
 void LCD_SetXY(uint16_t x, uint16_t y);
 void LCD_SetRec(uint16_t xs, uint16_t xe, uint16_t ys, uint16_t ye);
 void LCD_DrawPoint(uint16_t x, uint16_t y, uint16_t color);
-void LCD_Clear(uint16_t color);
+void LCD_DrawLine(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2);
 void LCD_ShowChar(uint16_t x, uint16_t y, uint8_t num, uint8_t size, uint8_t mode);
 void LCD_ShowNum(uint16_t x, uint16_t y, uint32_t num, uint8_t len, uint8_t size, uint8_t dir, uint8_t mode);
 void LCD_ShowString(uint16_t x, uint16_t y, char *str, uint8_t size, uint8_t dir, uint8_t mode);
diff --git a/src/tftlcd.c b/src/tftlcd.c
index cac27f8..1b59a47 100644
--- a/src/tftlcd.c
+++ b/src/tftlcd.c
@@ -147,7 +147,11 @@ void LCD_Init() {
     LCD_WR_DATA(0XC1);
 
     LCD_WR_REG(LCD_RAM_AC);
-    LCD_WR_DATA(0x08);  // 0x88: MY = MX = MV = 0 从左到右 从上到下, BGR = 1s
+#if USE_HORIZONTAL == 1
+    LCD_WR_DATA(0x88);  // 0x08: MY = 1, MX = MV = 0 从左到右 从下到下, BGR = 1s
+#else
+    LCD_WR_DATA(0x08);  // 0x08: MY = MX = MV = 0 从左到右 从上到下, BGR = 1s
+#endif
 
     LCD_WR_REG(0x3A);
     LCD_WR_DATA(0x55);
@@ -205,7 +209,7 @@ void LCD_Init() {
     LCD_WR_REG(0x29);  // Display on
 
     LCD_BL_CLR;  // Back Light On
-    LCD_Clear(BACK_COLOR);
+    LCD_Clear();
 }
 
 void LCD_SetColor(uint16_t color) { PEN_COLOR = color; }
@@ -248,14 +252,45 @@ void LCD_DrawPoint(uint16_t x, uint16_t y, uint16_t color) {
     LCD_WR_REG_DATA_16BIT(LCD_RAM_WR, color);
 }
 
-void LCD_Clear(uint16_t color) {
+void LCD_DrawLine(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2) {
+    uint16_t x, y, d, dx, dy, xe, ye, Dx, Dy;
+
+    xe = ye = 0;
+    x = x1, y = y1;
+    Dx = x2 - x1, Dy = y2 - y1;
+
+    if (Dx > 0) dx = 1;
+    else if (Dx == 0) dx = 0;
+    else {
+        dx = -1;
+        Dx = -Dx;
+    }
+    if (Dy > 0) dy = 1;
+    else if (Dy == 0) dy = 0;
+    else {
+        dy = -1;
+        Dy = -Dy;
+    }
+    if (Dx > Dy) d = Dx;
+    else d = Dy;
+
+    for (uint16_t i = 0; i <= d + 1; i++)  // 画线输出
+    {
+        LCD_DrawPoint(x, y, PEN_COLOR);  // 画点
+        xe += Dx, ye += Dy;
+        if (xe > d) xe -= d, x += dx;
+        if (ye > d) ye -= d, y += dy;
+    }
+}
+
+void LCD_Clear() {
     LCD_SetRec(0, LCD_W - 1, 0, LCD_H - 1);
     LCD_WR_REG(LCD_RAM_WR);
-    for (uint32_t i = 0; i < LCD_W * LCD_H; i++) LCD_WR_DATA_16BIT(color);
+    for (uint32_t i = 0; i < LCD_W * LCD_H; i++) LCD_WR_DATA_16BIT(BACK_COLOR);
     // for (uint16_t i = 0; i < LCD_W; i++)
     //     for (uint16_t j = 0; j < LCD_H; j++) {
     //         LCD_SetXY(i, j);
-    //         LCD_WR_REG_DATA_16BIT(LCD_RAM_WR, color);
+    //         LCD_WR_REG_DATA_16BIT(LCD_RAM_WR, BACK_COLOR);
     //     }
 }