added x11 display driver port (#300)

Co-authored-by: Gregor Copoix <gregor.copoix@ithinx.io>

.gitignore

@@ -1,2 +1,3 @@
 **/*.o
-**/*.d
+**/*.d
+build/*

lv_drv_conf_template.h

@@ -195,6 +195,13 @@
 #  endif
 #endif
 
+/*----------------------------------------
+ *  X11 drivers (monitor, mouse, keyboard)
+ *---------------------------------------*/
+#ifndef USE_X11
+#  define USE_X11       0
+#endif
+
 /*----------------
  *    SSD1963
  *--------------*/

x11/x11.c

@@ -0,0 +1,281 @@
+/**
+ * @file x11.c
+ *
+ */
+
+/*********************
+ *      INCLUDES
+ *********************/
+#include "x11.h"
+#if USE_X11
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+/*********************
+ *      DEFINES
+ *********************/
+#ifndef KEYBOARD_BUFFER_SIZE
+  #define KEYBOARD_BUFFER_SIZE 64
+#endif
+
+#define MIN(A, B) ((A) < (B) ? (A) : (B))
+#define MAX(A, B) ((A) > (B) ? (A) : (B))
+
+#ifndef X11_OPTIMIZED_SCREEN_UPDATE
+  #define X11_OPTIMIZED_SCREEN_UPDATE 1
+#endif
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+/**********************
+ *  STATIC VARIABLES
+ **********************/
+static Display*    display = NULL;
+static Window      window = (XID)-1;
+static GC          gc = NULL;
+static XImage*     ximage = NULL;
+static lv_timer_t* timer = NULL;
+
+static char        kb_buffer[KEYBOARD_BUFFER_SIZE];
+static lv_point_t  mouse_pos = { 0, 0 };
+static bool        left_mouse_btn = false;
+static bool        right_mouse_btn = false;
+static bool        wheel_mouse_btn = false;
+static int16_t     wheel_cnt = 0;
+
+/**********************
+ *      MACROS
+ **********************/
+
+/**********************
+ *   STATIC FUNCTIONS
+ **********************/
+static int predicate(Display* disp, XEvent* evt, XPointer arg) { return 1; }
+
+static void x11_event_handler(lv_timer_t * t)
+{
+    XEvent myevent;
+    KeySym mykey;
+    int n;
+
+    /* handle all outstanding X events */
+    while (XCheckIfEvent(display, &myevent, predicate, NULL)) {
+        switch(myevent.type)
+        {
+        case Expose:
+            if(myevent.xexpose.count==0)
+            {
+                XPutImage(display, window, gc, ximage, 0, 0, 0, 0, LV_HOR_RES, LV_VER_RES);
+            }
+            break;
+        case MotionNotify:
+            mouse_pos.x = myevent.xmotion.x;
+            mouse_pos.y = myevent.xmotion.y;
+            break;
+        case ButtonPress:
+            switch (myevent.xbutton.button)
+            {
+            case Button1:
+                left_mouse_btn = true;
+                break;
+            case Button2:
+                wheel_mouse_btn = true;
+                break;
+            case Button3:
+                right_mouse_btn = true;
+                break;
+            case Button4:
+                wheel_cnt--; // Scrolled up
+                break;
+            case Button5:
+                wheel_cnt++; // Scrolled down
+                break;
+            default:
+                LV_LOG_WARN("unhandled button press : %d", myevent.xbutton.button);
+            }
+            break;
+        case ButtonRelease:
+            switch (myevent.xbutton.button)
+            {
+            case Button1:
+                left_mouse_btn = false;
+                break;
+            case Button2:
+                wheel_mouse_btn = false;
+                break;
+            case Button3:
+                right_mouse_btn = false;
+                break;
+            }
+            break;
+        case KeyPress:
+            n = XLookupString(&myevent.xkey, &kb_buffer[0], sizeof(kb_buffer), &mykey, NULL);
+            kb_buffer[n] = '\0';
+            break;
+        case KeyRelease:
+            break;
+        default:
+            LV_LOG_WARN("unhandled x11 event: %d", myevent.type);
+        }
+    }
+}
+
+static void lv_x11_hide_cursor()
+{
+    XColor black = { .red = 0, .green = 0, .blue = 0 };
+    char empty_data[] = { 0 };
+
+    Pixmap empty_bitmap = XCreateBitmapFromData(display, window, empty_data, 1, 1);
+    Cursor inv_cursor = XCreatePixmapCursor(display, empty_bitmap, empty_bitmap, &black, &black, 0, 0);
+    XDefineCursor(display, window, inv_cursor);
+    XFreeCursor(display, inv_cursor);
+    XFreePixmap(display, empty_bitmap);
+}
+
+
+/**********************
+ *   GLOBAL FUNCTIONS
+ **********************/
+
+void lv_x11_flush(lv_disp_drv_t *disp_drv, const lv_area_t *area, lv_color_t *color_p)
+{
+#if X11_OPTIMIZED_SCREEN_UPDATE
+    static const lv_area_t inv_area = { .x1 = 0xFFFF,
+                                        .x2 = 0,
+                                        .y1 = 0xFFFF,
+                                        .y2 = 0
+                                      };
+    static lv_area_t upd_area = inv_area;
+
+    /* build display update area until lv_disp_flush_is_last */
+    upd_area.x1 = MIN(upd_area.x1, area->x1);
+    upd_area.x2 = MAX(upd_area.x2, area->x2);
+    upd_area.y1 = MIN(upd_area.y1, area->y1);
+    upd_area.y2 = MAX(upd_area.y2, area->y2);
+#endif // X11_OPTIMIZED_SCREEN_UPDATE
+
+    for (lv_coord_t y = area->y1; y <= area->y2; y++)
+    {
+        uint32_t  dst_offs = area->x1 + y * LV_HOR_RES;
+        uint32_t* dst_data = &((uint32_t*)ximage->data)[dst_offs];
+        for (lv_coord_t x = area->x1; x <= area->x2; x++, color_p++, dst_data++)
+        {
+            *dst_data = lv_color_to32(*color_p);
+        }
+    }
+
+    if (lv_disp_flush_is_last(disp_drv))
+    {
+#if X11_OPTIMIZED_SCREEN_UPDATE
+        /* refresh collected display update area only */
+        lv_coord_t upd_w = upd_area.x2 - upd_area.x1 + 1;
+        lv_coord_t upd_h = upd_area.y2 - upd_area.y1 + 1;
+        XPutImage(display, window, gc, ximage, upd_area.x1, upd_area.y1, upd_area.x1, upd_area.y1, upd_w, upd_h);
+        /* invalidate collected area */
+        upd_area = inv_area;
+#else
+        /* refresh full display */
+        XPutImage(display, window, gc, ximage, 0, 0, 0, 0, LV_HOR_RES, LV_VER_RES);
+#endif
+    }
+    lv_disp_flush_ready(disp_drv);
+}
+
+void lv_x11_get_pointer(lv_indev_drv_t *indev_drv, lv_indev_data_t *data)
+{
+    (void) indev_drv; // Unused
+
+    data->point = mouse_pos;
+    data->state = left_mouse_btn ? LV_INDEV_STATE_PRESSED : LV_INDEV_STATE_RELEASED;
+
+}
+
+void lv_x11_get_mousewheel(lv_indev_drv_t *indev_drv, lv_indev_data_t *data)
+{
+    (void) indev_drv; // Unused
+
+    data->state = wheel_mouse_btn ? LV_INDEV_STATE_PRESSED : LV_INDEV_STATE_RELEASED;
+    data->enc_diff = wheel_cnt;
+    wheel_cnt = 0;
+}
+
+void lv_x11_get_keyboard(lv_indev_drv_t *indev_drv, lv_indev_data_t *data)
+{
+    (void) indev_drv; // Unused
+
+    size_t len = strlen(kb_buffer);
+    if (len > 0)
+    {
+        data->state = LV_INDEV_STATE_PRESSED;
+        data->key = kb_buffer[0];
+        memmove(kb_buffer, kb_buffer + 1, len);
+        data->continue_reading = (len > 0);
+    }
+    else
+    {
+        data->state = LV_INDEV_STATE_RELEASED;
+    }
+}
+
+void lv_x11_init(char const* title, lv_coord_t width, lv_coord_t height)
+{
+    /* setup display/screen */
+    display = XOpenDisplay(NULL);
+    int screen = DefaultScreen(display);
+
+    /* drawing contexts for an window */
+    unsigned long myforeground = BlackPixel(display, screen);
+    unsigned long mybackground = WhitePixel(display, screen);
+
+    /* create window */
+    window = XCreateSimpleWindow(display, DefaultRootWindow(display),
+                                   0, 0, width, height,
+                                   0, myforeground, mybackground);
+
+    /* window manager properties (yes, use of StdProp is obsolete) */
+	XSetStandardProperties(display, window, title, NULL, None, NULL, 0, NULL);
+
+    /* allow receiving mouse and keyboard events */
+    XSelectInput(display, window, PointerMotionMask|ButtonPressMask|ButtonReleaseMask|KeyPressMask|KeyReleaseMask|ExposureMask);
+
+    /* graphics context */
+    gc = XCreateGC(display, window, 0, 0);
+
+    lv_x11_hide_cursor();
+
+    /* create cache XImage */
+    Visual* visual = XDefaultVisual(display, screen);
+    int dplanes = DisplayPlanes(display, screen);
+    ximage = XCreateImage(display, visual, dplanes, ZPixmap, 0,
+                          malloc(width * height * sizeof(uint32_t)), width, height, 32, 0);
+
+    timer = lv_timer_create(x11_event_handler, 10, NULL);
+
+	/* finally bring window on top of the other windows */
+    XMapRaised(display, window);
+}
+
+void lv_x11_deinit(void)
+{
+    lv_timer_del(timer);
+
+    free(ximage->data);
+
+    XDestroyImage(ximage);
+    ximage = NULL;
+
+    XFreeGC(display, gc);
+    gc = NULL;
+    XDestroyWindow(display, window);
+    window = (XID)-1;
+
+    XCloseDisplay(display);
+    display = NULL;
+}
+
+#endif // USE_X11

x11/x11.h

@@ -0,0 +1,60 @@
+/**
+ * @file x11.h
+ *
+ */
+
+#ifndef X11_H
+#define X11_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*********************
+ *      INCLUDES
+ *********************/
+#ifndef LV_DRV_NO_CONF
+  #ifdef LV_CONF_INCLUDE_SIMPLE
+    #include "lv_drv_conf.h"
+  #else
+    #include "../../lv_drv_conf.h"
+  #endif
+#endif
+
+#if USE_X11
+
+#ifdef LV_LVGL_H_INCLUDE_SIMPLE
+  #include "lvgl.h"
+#else
+  #include "lvgl/lvgl.h"
+#endif
+
+/*********************
+ *      DEFINES
+ *********************/
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+/**********************
+ * GLOBAL PROTOTYPES
+ **********************/
+void lv_x11_init(char const* title, lv_coord_t width, lv_coord_t height);
+void lv_x11_deinit(void);
+void lv_x11_flush(lv_disp_drv_t *disp_drv, const lv_area_t *area, lv_color_t *color_p);
+void lv_x11_get_pointer(lv_indev_drv_t *indev_drv, lv_indev_data_t *data);
+void lv_x11_get_mousewheel(lv_indev_drv_t *indev_drv, lv_indev_data_t *data);
+void lv_x11_get_keyboard(lv_indev_drv_t *indev_drv, lv_indev_data_t *data);
+
+/**********************
+ *      MACROS
+ **********************/
+
+#endif /* USE_X11 */
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif /* X11_H */