From 07c62a849aa9c898d6a1d16481911883fdbc0687 Mon Sep 17 00:00:00 2001
From: Jonathan Williamson <jon@pimoroni.com>
Date: Mon, 21 Feb 2022 17:42:29 +0000
Subject: [PATCH] added rotation by angle in degrees to text() and glyph()
 methods

---
 examples/badger2040/badger2040_fonts.cpp |  1 +
 libraries/badger2040/badger2040.cpp      | 30 ++++++++++++++++++++----
 libraries/badger2040/badger2040.hpp      |  4 ++--
 3 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/examples/badger2040/badger2040_fonts.cpp b/examples/badger2040/badger2040_fonts.cpp
index 1dab94a0..c6bb729a 100644
--- a/examples/badger2040/badger2040_fonts.cpp
+++ b/examples/badger2040/badger2040_fonts.cpp
@@ -65,6 +65,7 @@ int main() {
   printf("\n\n=======\nbadger2040 starting up\n\n");
 
   badger.init();
+  badger.update_speed(1);
 
   uint32_t i = 0;
 
diff --git a/libraries/badger2040/badger2040.cpp b/libraries/badger2040/badger2040.cpp
index 7b2ae398..dbe4795f 100644
--- a/libraries/badger2040/badger2040.cpp
+++ b/libraries/badger2040/badger2040.cpp
@@ -194,7 +194,11 @@ namespace pimoroni {
     return &_font->chars[c - 32];
   }
 
-  int32_t Badger2040::glyph(unsigned char c, int32_t x, int32_t y, float s) {
+  inline float deg2rad(float degrees) {
+    return (degrees * M_PI) / 180.0f;
+  }
+
+  int32_t Badger2040::glyph(unsigned char c, int32_t x, int32_t y, float s, float a) {
     // if space character then return a width to move the caret by
     const hershey_font_glyph_t *gd = glyph_data(c);
 
@@ -203,6 +207,10 @@ namespace pimoroni {
       return 0;
     }
 
+    a = deg2rad(a);
+    float as = sin(a);
+    float ac = cos(a);
+
     const int8_t *pv = gd->vertices;
     int8_t cx = (*pv++) * s;
     int8_t cy = (*pv++) * s;
@@ -216,8 +224,14 @@ namespace pimoroni {
         int8_t nx = (*pv++) * s;
         int8_t ny = (*pv++) * s;
 
+        int rcx = cx * ac - cy * as;
+        int rcy = cx * as + cy * ac;
+
+        int rnx = nx * ac - ny * as;
+        int rny = nx * as + ny * ac;
+
         if(pen_down) {
-          line(cx + x, cy + y, nx + x, ny + y);
+          line(rcx + x, rcy + y, rnx + x, rny + y);
         }
 
         cx = nx;
@@ -229,12 +243,20 @@ namespace pimoroni {
     return gd->width * s;
   }
 
-  void Badger2040::text(std::string message, int32_t x, int32_t y, float s) {
+  void Badger2040::text(std::string message, int32_t x, int32_t y, float s, float a) {
     int32_t cx = x;
     int32_t cy = y;
 
+    int32_t ox = 0;
+
+    float as = sin(deg2rad(a));
+    float ac = cos(deg2rad(a));
+
     for(auto &c : message) {
-      cx += glyph(c, cx, cy, s);
+      int rcx = ox * ac;
+      int rcy = ox * as;
+
+      ox += glyph(c, cx + rcx, cy + rcy, s, a);
     }
   }
 
diff --git a/libraries/badger2040/badger2040.hpp b/libraries/badger2040/badger2040.hpp
index 29b4f14b..1eb608d1 100644
--- a/libraries/badger2040/badger2040.hpp
+++ b/libraries/badger2040/badger2040.hpp
@@ -55,9 +55,9 @@ namespace pimoroni {
     void image(const uint8_t *data);
 
     // text (fonts: sans, sans_bold, gothic, cursive_bold, cursive, serif_italic, serif, serif_bold)
-    void text(std::string message, int32_t x, int32_t y, float s = 1.0f);
+    void text(std::string message, int32_t x, int32_t y, float s = 1.0f, float a = 0.0f);
     const hershey_font_glyph_t* glyph_data(unsigned char c);
-    int32_t glyph(unsigned char c, int32_t x, int32_t y, float s);
+    int32_t glyph(unsigned char c, int32_t x, int32_t y, float s, float a = 0.0f);
 
     void debug_command(uint8_t command, size_t len, const uint8_t *data);
     void dump_otp(uint8_t *otp_data);