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@ethinx
Created July 9, 2023 03:22
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make it easier to understand the position of sprite and its pivot in demo https://github.com/Bodmer/TFT_eSPI/blob/master/examples/Sprite/Rotated_Sprite_1/Rotated_Sprite_1.ino
// This example plots a rotated Sprite to the screen using the pushRotated()
// function. It is written for a 240 x 320 TFT screen.
// Two rotation pivot points must be set, one for the Sprite and one for the TFT
// using setPivot(). These pivot points do not need to be within the visible screen
// or Sprite boundary.
// When the Sprite is rotated and pushed to the TFT with pushRotated(angle) it will be
// drawn so that the two pivot points coincide. This makes rotation about a point on the
// screen very simple. The rotation is clockwise with increasing angle. The angle is in
// degrees, an angle of 0 means no Sprite rotation.
// The pushRotated() function works with 1, 4, 8 and 16 bit per pixel (bpp) Sprites.
// The original Sprite is unchanged so can be plotted again at a different angle.
// Optionally a transparent colour can be defined, pixels of this colour will
// not be plotted to the TFT.
// For 1 bpp Sprites the foreground and background colours are defined with the
// function spr.setBitmapColor(foregroundColor, backgroundColor).
// For 4 bpp Sprites the colour map index is used instead of the 16 bit colour
// e.g. spr.setTextColor(5); // Green text in default colour map
// See "Transparent_Sprite_Demo_4bit" example for default colour map details
// Created by Bodmer 6/1/19 as an example to the TFT_eSPI library:
// https://github.com/Bodmer/TFT_eSPI
#include <TFT_eSPI.h>
TFT_eSPI tft = TFT_eSPI(); // TFT object
TFT_eSprite spr = TFT_eSprite(&tft); // Sprite object
// =======================================================================================
// Setup
// =======================================================================================
void setup() {
Serial.begin(250000); // Debug only
tft.begin(); // initialize
tft.setRotation(0);
}
// =======================================================================================
// Loop
// =======================================================================================
void loop() {
int xw = tft.width()/2; // xw, yh is middle of screen
int yh = tft.height()/2;
showMessage("90 degree angles");
tft.setPivot(xw, yh); // Set pivot to middle of TFT screen
drawX(xw, yh); // Show where screen pivot is
// // Create the Sprite
spr.setColorDepth(8); // Create an 8bpp Sprite of 60x30 pixels
spr.createSprite(64, 30); // 8bpp requires 64 * 30 = 1920 bytes
spr.setPivot(32,55); // Set pivot relative to top left corner of Sprite
spr.fillSprite(TFT_BLACK); // Fill the Sprite with black
spr.pushRotated(0);
spr.pushRotated(90);
tft.fillCircle(xw, yh-25, 3, TFT_RED);
tft.fillCircle(xw-32, yh-55, 3, TFT_GREEN);
tft.fillCircle(xw, yh-40, 3, TFT_BLUE);
delay(10000); // Pause so we see it
showMessage("Transparent rotations");
tft.fillCircle(xw, yh, 70, TFT_DARKGREY); // Draw a filled circle
tft.setPivot(xw, yh); // Set pivot to middle of screen
drawX(xw, yh); // Show where pivot is
spr.deleteSprite();
spr.setColorDepth(8); // Create a 8bpp Sprite
spr.createSprite(40, 30); // Create a new Sprite 40x30
spr.setPivot(-75, 15); // Set Sprite pivot at -75,15
spr.fillSprite(TFT_BLACK); // Clear the Sprite
spr.pushRotated(-90);
tft.fillCircle(xw, yh-75, 3, TFT_RED);
tft.fillCircle(xw, yh-95, 3, TFT_PURPLE);
tft.fillCircle(xw, yh-70, 3, TFT_GREEN);
delay(10000); // Pause so we see it
spr.deleteSprite();
}
// =======================================================================================
// Draw an X centered on x,y
// =======================================================================================
void drawX(int x, int y)
{
tft.drawLine(x-5, y-5, x+5, y+5, TFT_WHITE);
tft.drawLine(x-5, y+5, x+5, y-5, TFT_WHITE);
}
// =======================================================================================
// Show a message at the top of the screen
// =======================================================================================
void showMessage(String msg)
{
// Clear the screen areas
tft.fillRect(0, 0, tft.width(), 20, TFT_BLACK);
tft.fillRect(0, 20, tft.width(), tft.height()-20, TFT_BLUE);
uint8_t td = tft.getTextDatum(); // Get current datum
tft.setTextDatum(TC_DATUM); // Set new datum
tft.drawString(msg, tft.width()/2, 2, 2); // Message in font 2
tft.setTextDatum(td); // Restore old datum
}
// =======================================================================================
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