examples: Added misc/02-clipboard

examples/CMakeLists.txt

@@ -155,6 +155,7 @@ add_sdl_example_executable(camera-read-and-draw SOURCES camera/01-read-and-draw/
 add_sdl_example_executable(pen-drawing-lines SOURCES pen/01-drawing-lines/drawing-lines.c)
 add_sdl_example_executable(asyncio-load-bitmaps SOURCES asyncio/01-load-bitmaps/load-bitmaps.c DATAFILES ${CMAKE_CURRENT_SOURCE_DIR}/../test/sample.bmp ${CMAKE_CURRENT_SOURCE_DIR}/../test/gamepad_front.bmp ${CMAKE_CURRENT_SOURCE_DIR}/../test/speaker.bmp ${CMAKE_CURRENT_SOURCE_DIR}/../test/icon2x.bmp)
 add_sdl_example_executable(misc-power SOURCES misc/01-power/power.c)
+add_sdl_example_executable(misc-clipboard SOURCES misc/02-clipboard/clipboard.c)
 add_sdl_example_executable(demo-snake SOURCES demo/01-snake/snake.c)
 add_sdl_example_executable(demo-woodeneye-008 SOURCES demo/02-woodeneye-008/woodeneye-008.c)
 add_sdl_example_executable(demo-infinite-monkeys SOURCES demo/03-infinite-monkeys/infinite-monkeys.c)

examples/misc/02-clipboard/README.txt

@@ -0,0 +1,6 @@
+This example code lets the user copy and paste with the system clipboard.
+
+This only handles text, but SDL supports other data types, too.
+
+Note that only Chrome-based browsers support this API currently. This uses a
+new Javascript API, so hopefully this will be available everywhere soon!

examples/misc/02-clipboard/clipboard.c

@@ -0,0 +1,235 @@
+/*
+ * This example code lets the user copy and paste with the system clipboard.
+ *
+ * This only handles text, but SDL supports other data types, too.
+ *
+ * This code is public domain. Feel free to use it for any purpose!
+ */
+
+#define SDL_MAIN_USE_CALLBACKS 1  /* use the callbacks instead of main() */
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_main.h>
+
+#include "../../save-rendering-to-bitmaps.h"
+
+/* We will use this renderer to draw into this window every frame. */
+static SDL_Window *window = NULL;
+static SDL_Renderer *renderer = NULL;
+static const char *copybuttonstr = "Click here to copy!";
+static const char *pastebuttonstr = "Click here to paste!";
+static SDL_FRect currenttimerect;
+static SDL_FRect copybuttonrect;
+static SDL_FRect pastetextrect;
+static SDL_FRect pastebuttonrect;
+static bool copy_pressed = false;
+static bool paste_pressed = false;
+static char current_time[64];
+static char *pasted_str = NULL;
+
+static void CalculateCurrentTimeString(void)
+{
+    SDL_Time ticks = 0;
+    SDL_DateTime dt;
+    if (!SDL_GetCurrentTime(&ticks) || !SDL_TimeToDateTime(ticks, &dt, true)) {
+        SDL_snprintf(current_time, sizeof (current_time), "(Don't know the current time, sorry.)");
+    } else {
+        static const char *month[12] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" };
+        static const char *day[7] = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" };
+        SDL_snprintf(current_time, sizeof (current_time), "%s, %s %d, %d   %02d:%02d:%02d", day[dt.day_of_week], month[dt.month-1], dt.day, dt.year, dt.hour, dt.minute, dt.second);
+    }
+}
+
+/* This function runs once at startup. */
+SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[])
+{
+    SDL_SetAppMetadata("Example Misc Clipboard", "1.0", "com.example.misc-clipboard");
+
+    if (!SDL_Init(SDL_INIT_VIDEO)) {
+        SDL_Log("Couldn't initialize SDL: %s", SDL_GetError());
+        return SDL_APP_FAILURE;
+    }
+
+    if (!SDL_CreateWindowAndRenderer("examples/misc/clipboard", 640, 480, 0, &window, &renderer)) {
+        SDL_Log("Couldn't create window/renderer: %s", SDL_GetError());
+        return SDL_APP_FAILURE;
+    }
+
+    CalculateCurrentTimeString();
+
+    /* set up the locations where we'll draw stuff. */
+    currenttimerect.x = 30;
+    currenttimerect.y = 10;
+    currenttimerect.w = 390;
+    currenttimerect.h = SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE + 10;
+
+    copybuttonrect.x = currenttimerect.x + currenttimerect.w + 30;
+    copybuttonrect.y = currenttimerect.y;
+    copybuttonrect.w = (SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE * SDL_strlen(copybuttonstr)) + 10;
+    copybuttonrect.h = currenttimerect.h;
+
+    pastetextrect.x = 10;
+    pastetextrect.y = currenttimerect.y + currenttimerect.h + 10;
+    pastetextrect.w = 620;
+    pastetextrect.h = ((480 - pastetextrect.y) - copybuttonrect.h) - 20;
+
+    pastebuttonrect.w = (SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE * SDL_strlen(pastebuttonstr)) + 10;
+    pastebuttonrect.x = (640 - pastebuttonrect.w) / 2.0f;
+    pastebuttonrect.y = pastetextrect.y + pastetextrect.h + 10;
+    pastebuttonrect.h = copybuttonrect.h;
+
+    return SDL_APP_CONTINUE;  /* carry on with the program! */
+}
+
+/* This function runs when a new event (mouse input, keypresses, etc) occurs. */
+SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event)
+{
+    if (event->type == SDL_EVENT_QUIT) {
+        return SDL_APP_SUCCESS;  /* end the program, reporting success to the OS. */
+    } else if (event->type == SDL_EVENT_MOUSE_BUTTON_DOWN) {
+        if (event->button.button == SDL_BUTTON_LEFT) {
+            const SDL_FPoint p = { event->button.x, event->button.y };
+            copy_pressed = SDL_PointInRectFloat(&p, &copybuttonrect);
+            paste_pressed = SDL_PointInRectFloat(&p, &pastebuttonrect);
+        }
+    } else if (event->type == SDL_EVENT_MOUSE_BUTTON_UP) {
+        if (event->button.button == SDL_BUTTON_LEFT) {
+            const SDL_FPoint p = { event->button.x, event->button.y };
+            if (copy_pressed && SDL_PointInRectFloat(&p, &copybuttonrect)) {
+                SDL_SetClipboardText(current_time);
+            } else if (paste_pressed && SDL_PointInRectFloat(&p, &pastebuttonrect)) {
+                SDL_free(pasted_str);
+                pasted_str = SDL_GetClipboardText();
+            }
+            copy_pressed = paste_pressed = false;
+        }
+    }
+
+    return SDL_APP_CONTINUE;  /* carry on with the program! */
+}
+
+static void RenderPastedText(void)
+{
+    char *str = pasted_str;
+    if (str) {
+        float x = pastetextrect.x + 5;
+        float y = pastetextrect.y + 5;
+        const float w = pastetextrect.w - 10;
+        const float h = pastetextrect.h;
+        const size_t max_chars_per_line = (size_t) (w / SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE);
+        char *newline;
+        size_t slen;
+        char ch;
+
+        /* this doesn't wordwrap, or deal with Unicode....this is just a simple example app! */
+        while ((newline = SDL_strchr(str, '\n')) != NULL) {
+            const bool ignore_cr = ((newline > str) && (newline[-1] == '\r'));
+
+            if (ignore_cr) {
+                newline[-1] = '\0';
+            }
+            *newline = '\0';
+
+            slen = SDL_strlen(str);  /* length to end of line. */
+            slen = SDL_min(slen, max_chars_per_line);
+            ch = str[slen];
+            str[slen] = '\0';
+            SDL_RenderDebugText(renderer, x, y, str);
+            str[slen] = ch;
+
+            if (ignore_cr) {
+                newline[-1] = '\r';
+            }
+            *newline = '\n';
+
+            str = newline + 1;
+            y += (SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE + 2);
+            if ((h - y) < SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE) {
+                break;  // no space for another line, stop here.
+            }
+        }
+
+        /* last text after newline, if there's room. */
+        if ((h - y) >= SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE) {
+            slen = SDL_strlen(str);  /* length to end of line. */
+            slen = SDL_min(slen, max_chars_per_line);
+            ch = str[slen];
+            str[slen] = '\0';
+            SDL_RenderDebugText(renderer, x, y, str);
+            str[slen] = ch;
+        }
+    }
+}
+
+/* This function runs once per frame, and is the heart of the program. */
+SDL_AppResult SDL_AppIterate(void *appstate)
+{
+    float x, y;
+
+    CalculateCurrentTimeString();
+
+    SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);  /* black */
+    SDL_RenderClear(renderer);
+
+    /* draw a frame around the current time. */
+    SDL_SetRenderDrawColor(renderer, 0, 0, 255, 255);
+    SDL_RenderFillRect(renderer, &currenttimerect);
+    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+    SDL_RenderRect(renderer, &currenttimerect);
+
+    /* draw the current time inside the frame. */
+    x = currenttimerect.x + ((currenttimerect.w - (SDL_DEBUG_TEXT_FONT_CHARACTER_SIZE * SDL_strlen(current_time))) / 2.0f);
+    y = currenttimerect.y + 5;
+    SDL_SetRenderDrawColor(renderer, 255, 255, 0, 255);
+    SDL_RenderDebugText(renderer, x, y, current_time);
+
+    /* draw a frame for the "copy the current time to the clipboard" button. */
+    if (copy_pressed) {
+        SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);
+    } else {
+        SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
+    }
+    SDL_RenderFillRect(renderer, &copybuttonrect);
+    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+    SDL_RenderRect(renderer, &copybuttonrect);
+
+    /* draw the "copy this text" button string. */
+    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+    SDL_RenderDebugText(renderer, copybuttonrect.x + 5, copybuttonrect.y + 5, copybuttonstr);
+
+    /* draw a frame for the pasted text area. */
+    SDL_SetRenderDrawColor(renderer, 0, 53, 25, 255);
+    SDL_RenderFillRect(renderer, &pastetextrect);
+    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+    SDL_RenderRect(renderer, &pastetextrect);
+
+    /* draw pasted text. */
+    SDL_SetRenderDrawColor(renderer, 0, 219, 107, 255);
+    RenderPastedText();
+
+    /* draw a frame for the "paste from the clipboard" button. */
+    if (paste_pressed) {
+        SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);
+    } else {
+        SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
+    }
+    SDL_RenderFillRect(renderer, &pastebuttonrect);
+    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+    SDL_RenderRect(renderer, &pastebuttonrect);
+
+    /* draw the "paste some text" button string. */
+    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
+    SDL_RenderDebugText(renderer, pastebuttonrect.x + 5, pastebuttonrect.y + 5, pastebuttonstr);
+
+    /* put the new rendering on the screen. */
+    SDL_RenderPresent(renderer);
+
+    return SDL_APP_CONTINUE;  /* carry on with the program! */
+}
+
+/* This function runs once at shutdown. */
+void SDL_AppQuit(void *appstate, SDL_AppResult result)
+{
+    SDL_free(pasted_str);
+    /* SDL will clean up the window/renderer for us. */
+}
+