From 99b6a5ac4ac299e2768f1d05833cbbabe1543586 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franti=C5=A1ek=20Boh=C3=A1=C4=8Dek?=
 <fandabohacek@gmail.com>
Date: Mon, 14 Jun 2021 21:35:09 +0200
Subject: [PATCH] feat: add display utils functions

---
 image-viewer/include/display_utils.h | 60 +++++++++++++++++++++++++
 image-viewer/src/display_utils.c     | 66 ++++++++++++++++++++++++++++
 2 files changed, 126 insertions(+)
 create mode 100644 image-viewer/include/display_utils.h
 create mode 100644 image-viewer/src/display_utils.c

diff --git a/image-viewer/include/display_utils.h b/image-viewer/include/display_utils.h
new file mode 100644
index 0000000000000000000000000000000000000000..30d7f00f775dc8385f0bb98410a7d82d3948e08b
--- /dev/null
+++ b/image-viewer/include/display_utils.h
@@ -0,0 +1,60 @@
+#ifndef __DISPLAY_UTILS_H__
+#define __DISPLAY_UTILS_H__
+
+#include <stdint.h>
+
+#define DISPLAY_MAX_RED 0x11111
+#define DISPLAY_MAX_GREEN 0x111111
+#define DISPLAY_MAX_BLUE 0x11111
+
+#define DISPLAY_WIDTH 480
+#define DISPLAY_HEIGHT 320
+
+typedef union {
+  struct {
+    uint8_t r : 5;
+    uint8_t g : 6;
+    uint8_t b : 5;
+  } fields;
+  uint16_t bits;
+} display_pixel_t;
+
+typedef struct {
+  uint8_t red;
+  uint8_t green;
+  uint8_t blue;
+} raw_pixel_onebit_t;
+
+typedef struct {
+  uint16_t red;
+  uint16_t green;
+  uint16_t blue;
+} raw_pixel_t;
+
+typedef struct {
+  void* base_address;
+} display_data_t;
+
+typedef struct {
+  display_pixel_t pixels[DISPLAY_HEIGHT * DISPLAY_WIDTH];
+  display_data_t data;
+} display_t;
+
+const display_pixel_t BLACK_PIXEL = { .bits = 0 };
+const display_pixel_t WHITE_PIXEL = { .bits = 0xFFFF };
+
+display_pixel_t raw_pixel_onebit_convert_to_display(raw_pixel_onebit_t pixel,
+                                             raw_pixel_onebit_t max);
+display_pixel_t raw_pixel_convert_to_display(raw_pixel_t pixel, raw_pixel_t max);
+
+display_t display_init(display_data_t data);
+void display_deinit(display_t *display);
+
+void display_render(display_t *display);
+void display_clear(display_t *display);
+
+display_pixel_t display_get_pixel(display_t *display, uint16_t x, uint16_t y);
+void display_set_pixel(display_t *display, uint16_t x, uint16_t y,
+                       display_pixel_t pixel);
+
+#endif // __DISPLAY_UTILS_H__
diff --git a/image-viewer/src/display_utils.c b/image-viewer/src/display_utils.c
new file mode 100644
index 0000000000000000000000000000000000000000..2eef1626f1237383b115545917ce147c121c4363
--- /dev/null
+++ b/image-viewer/src/display_utils.c
@@ -0,0 +1,66 @@
+#include "display_utils.h"
+#include "mzapo_parlcd.h"
+
+display_pixel_t raw_pixel_onebit_convert_to_display(raw_pixel_onebit_t pixel,
+                                                    raw_pixel_onebit_t max) {
+  display_pixel_t new = {
+      .fields = {
+          .r = ((double)pixel.red / (double)max.red) * DISPLAY_MAX_RED,
+          .g = ((double)pixel.green / (double)max.green) * DISPLAY_MAX_GREEN,
+          .b = ((double)pixel.blue / (double)max.blue) * DISPLAY_MAX_BLUE,
+      }};
+
+  return new;
+}
+
+display_pixel_t raw_pixel_convert_to_display(raw_pixel_t pixel,
+                                             raw_pixel_t max) {
+  display_pixel_t new = {
+      .fields = {
+          .r = ((double)pixel.red / (double)max.red) * DISPLAY_MAX_RED,
+          .g = ((double)pixel.green / (double)max.green) * DISPLAY_MAX_GREEN,
+          .b = ((double)pixel.blue / (double)max.blue) * DISPLAY_MAX_BLUE,
+      }
+  };
+
+  return new;
+}
+
+display_t display_init(display_data_t data) {
+  display_t display = {
+    .data = data
+  };
+  parlcd_hx8357_init(data.base_address);
+  display_clear(&display);
+
+  return display;
+}
+void display_deinit(display_t *display) {
+  display_clear(display);
+}
+
+void display_render(display_t *display) {
+  parlcd_write_cmd(display->data.base_address, PARLCD_CMD_FRAMEBUFFER);
+  int count = DISPLAY_HEIGHT * DISPLAY_WIDTH;
+  for (int i = 0; i < count; i++) {
+    parlcd_write_data(display->data.base_address, display->pixels[i].bits);
+  }
+}
+
+void display_clear(display_t *display) {
+  int count = DISPLAY_HEIGHT * DISPLAY_WIDTH;
+  for (int i = 0; i < count; i++) {
+    display->pixels[i] = BLACK_PIXEL;
+  }
+
+  display_render(display);
+}
+
+display_pixel_t display_get_pixel(display_t *display, uint16_t x, uint16_t y) {
+  return display->pixels[y * DISPLAY_WIDTH + x];
+}
+
+void display_set_pixel(display_t *display, uint16_t x, uint16_t y,
+                       display_pixel_t pixel) {
+  display->pixels[y * DISPLAY_WIDTH + x] = pixel;
+}