Implement interactive demo program

Makefile

@@ -21,7 +21,7 @@ INC_FLAGS := $(addprefix -I,$(INC_DIRS))
 STATIC_LIB := $(LIB_DIR)/libresynthesizer.a
 
 EXAMPLE_DIR := examples
-EXAMPLES := $(EXAMPLE_DIR)/dummy $(EXAMPLE_DIR)/ppm
+EXAMPLES := $(EXAMPLE_DIR)/hello $(EXAMPLE_DIR)/ppm $(EXAMPLE_DIR)/painter
 
 # -g -Wall -Wextra -Werror -std=c99 -pedantic-errors
 # TODO: Try both -Werror and -pedantic-errors after all the chores are done.
@@ -41,16 +41,21 @@ $(BUILD_DIR)/%.o: %.c
 	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@
 
 # Build the example executables.
-$(EXAMPLE_DIR)/dummy: examples/dummy.c $(STATIC_LIB)
+$(EXAMPLE_DIR)/hello: examples/hello.c $(STATIC_LIB)
 	@echo "\033[1;92mBuilding $@\033[0m"
 	mkdir -p $(dir $@)
-	$(CC) $(CFLAGS) -o $@ examples/dummy.c $(LDFLAGS) $(INC_FLAGS) $(STATIC_LIB)
+	$(CC) $(CFLAGS) -o $@ examples/hello.c $(LDFLAGS) $(INC_FLAGS) $(STATIC_LIB)
 
 $(EXAMPLE_DIR)/ppm: examples/ppm.c $(STATIC_LIB)
 	@echo "\033[1;92mBuilding $@\033[0m"
 	mkdir -p $(dir $@)
 	$(CC) $(CFLAGS) -o $@ examples/ppm.c $(LDFLAGS) $(INC_FLAGS) $(STATIC_LIB)
 
+$(EXAMPLE_DIR)/painter: examples/painter.c $(STATIC_LIB)
+	@echo "\033[1;92mBuilding $@\033[0m"
+	mkdir -p $(dir $@)
+	$(CC) $(CFLAGS) -o $@ examples/painter.c $(LDFLAGS) $(INC_FLAGS) $(STATIC_LIB) $(shell pkg-config --cflags --libs sdl2)
+
 # Run the executable(ppm) against the sample images with varying parameters.
 test: $(EXAMPLES)
 	echo "\033[1;92mTesting...\033[0m"

examples/dummy.c → examples/hello.c

@@ -1,4 +1,4 @@
-// examples/dummy.c
+// examples/hello.c
 #include <stdlib.h>
 #include <stdio.h>
 
@@ -15,13 +15,10 @@ int main()
 
     error = imageSynth(source_image_buffer, mask_image_buffer, T_RGB, params, NULL, NULL, &cancel_token);
 
-    if (error != 0)
-    {
-        printf("Task failed with the error code: %d\n", error);
-        exit(EXIT_FAILURE);
-    }
-
-    printf("Task finished\n");
+    // We're sending empty source/mask buffers.
+    // imageSynth() should return `IMAGE_SYNTH_ERROR_EMPTY_TARGET`
+    if (error == IMAGE_SYNTH_ERROR_EMPTY_TARGET)
+        puts("hello");
 
     return EXIT_SUCCESS;
 }

examples/painter.c

@@ -0,0 +1,181 @@
+/* examples/painter.c
+ *   $ ./painter source!
+ */
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "SDL2/SDL.h"
+
+#include "imageSynth.h"
+
+/* PPM(P6) Read/Write snippets
+ *
+ * Adopted from:
+ * https://github.com/skeeto/scratch/blob/master/animation/pixelsort.c
+ */
+struct ppm
+{
+    long width;
+    long height;
+    unsigned char data[];
+};
+
+static struct ppm *ppm_create(long width, long height)
+{
+    struct ppm *m = malloc(sizeof(*m) + width * height * 3);
+    m->width = width;
+    m->height = height;
+    return m;
+}
+
+static struct ppm *ppm_read(const char *filename)
+{
+    FILE *f = fopen(filename, "rb");
+    if (f == NULL)
+    {
+        perror(filename);
+        return NULL;
+    }
+    struct ppm *m;
+    long width, height;
+    if (fscanf(f, "P6 %ld%ld%*d%*c", &width, &height) < 2)
+    {
+        fprintf(stderr, "Not a valid PPM image.\n");
+        return NULL;
+    }
+    m = ppm_create(width, height);
+    fread(m->data, width * height, 3, f);
+    fclose(f);
+    return m;
+}
+
+SDL_Window *window = NULL;
+SDL_Surface *screen_surface = NULL;
+SDL_Surface *source_surface = NULL;
+SDL_Surface *mask_surface = NULL;
+SDL_Rect brush = {.x = 0, .y = 0, .w = 16, .h = 16};
+
+int main(int argc, char **argv)
+{
+    const char *source_in = argc > 1 ? argv[1] : NULL;
+    struct ppm *source_ppm = ppm_read(source_in);
+
+    if (source_ppm == NULL)
+    {
+        fprintf(stderr, "Source image not provided.\n");
+        exit(EXIT_FAILURE);
+    }
+
+    const int w = source_ppm->width;
+    const int h = source_ppm->width;
+    unsigned char *mask_surface_data = malloc(w * h * 4 * sizeof(*mask_surface_data));
+    unsigned char *mask_buffer_data = malloc(w * h * sizeof(*mask_buffer_data));
+
+    if (SDL_Init(SDL_INIT_VIDEO) != 0)
+    {
+        fprintf(stderr, "error %s \n", SDL_GetError());
+        exit(EXIT_FAILURE);
+    }
+
+    window = SDL_CreateWindow("resynthesizer", SDL_WINDOWPOS_UNDEFINED,
+                              SDL_WINDOWPOS_UNDEFINED, w, h, SDL_WINDOW_SHOWN);
+    screen_surface = SDL_GetWindowSurface(window);
+    source_surface = SDL_CreateRGBSurfaceFrom(
+        source_ppm->data, w, h, 24, w * 3, 0xFF, 0xFF00, 0xFF0000, 0);
+    mask_surface = SDL_CreateRGBSurfaceFrom(
+        mask_surface_data, w, h, 32, w * 4, 0xFF, 0xFF00, 0xFF0000, 0xFF000000);
+
+    ImageBuffer source_buffer = {
+        .data = source_ppm->data,
+        .width = w,
+        .height = h,
+        .rowBytes = w * 3,
+    };
+
+    ImageBuffer mask_buffer = {
+        .data = mask_buffer_data,
+        .width = w,
+        .height = h,
+        .rowBytes = w,
+    };
+
+    TImageSynthParameters params = {
+        .matchContextType = 1,
+        .mapWeight = 0.5f,
+        .sensitivityToOutliers = 0.117f,
+        .patchSize = 30,
+        .maxProbeCount = 200,
+    };
+
+    int cancel = 0;
+    bool is_running = true;
+    bool pressed = false;
+    SDL_Event event;
+
+    while (is_running)
+    {
+        while (SDL_PollEvent(&event))
+        {
+            switch (event.type)
+            {
+            case SDL_MOUSEMOTION:
+                brush.x = event.motion.x - brush.w / 2;
+                brush.y = event.motion.y - brush.h / 2;
+                if (!pressed)
+                    memset(mask_surface_data, 0, w * h * 4 * sizeof(char));
+                SDL_FillRect(mask_surface, &brush, SDL_MapRGB(mask_surface->format, 0xFF, 0xFF, 0xFF));
+                break;
+            case SDL_MOUSEBUTTONDOWN:
+                pressed = true;
+                SDL_FillRect(mask_surface, &brush, SDL_MapRGB(mask_surface->format, 0xFF, 0xFF, 0xFF));
+                break;
+            case SDL_MOUSEBUTTONUP:
+                pressed = false;
+                // Do the synthesis opration
+                for (int i = 0; i < w * h; ++i)
+                    mask_buffer_data[i] = mask_surface_data[i * 4];
+                imageSynth(&source_buffer, &mask_buffer, T_RGB, &params, NULL, NULL, &cancel);
+                memset(mask_surface_data, 0, w * h * 4 * sizeof(char));
+                break;
+            case SDL_KEYDOWN:
+                switch (event.key.keysym.sym)
+                {
+                case SDLK_ESCAPE:
+                    // Quit
+                    is_running = false;
+                    break;
+                case SDLK_r:
+                    // Reset source image
+                    break;
+                case SDLK_LEFTBRACKET:
+                    // Increase brush size
+                    brush.w--;
+                    brush.h--;
+                    break;
+                case SDLK_RIGHTBRACKET:
+                    // Decrease brush size
+                    brush.w++;
+                    brush.h++;
+                    break;
+                }
+                break;
+            }
+        }
+        SDL_BlitSurface(source_surface, NULL, screen_surface, NULL);
+        SDL_BlitSurface(mask_surface, NULL, screen_surface, NULL);
+        SDL_UpdateWindowSurface(window);
+        SDL_Delay(1);
+    }
+
+    SDL_FreeSurface(mask_surface);
+    SDL_FreeSurface(source_surface);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+
+    free(mask_buffer_data);
+    free(mask_surface_data);
+    free(source_ppm);
+
+    return EXIT_SUCCESS;
+}

examples/ppm.c

@@ -1,14 +1,14 @@
 /* examples/ppm.c
  *   $ ./ppm source! mask! result? context? neighbors? probes?
  */
-#include <stdlib.h>
 #include <stdio.h>
+#include <stdlib.h>
 
-#include <imageSynth.h>
+#include "imageSynth.h"
 
 /* PPM(P6) Read/Write snippets
  * 
- * Borrowed and modified from:
+ * Adopted from:
  * https://github.com/skeeto/scratch/blob/master/animation/pixelsort.c
  */
 struct ppm
@@ -18,25 +18,22 @@ struct ppm
     unsigned char data[];
 };
 
-static struct ppm *
-ppm_create(long width, long height)
+static struct ppm *ppm_create(long width, long height)
 {
     struct ppm *m = malloc(sizeof(*m) + width * height * 3);
     m->width = width;
     m->height = height;
     return m;
 }
 
-static void
-ppm_write(struct ppm *m, FILE *f)
+static void ppm_write(struct ppm *m, FILE *f)
 {
     fprintf(f, "P6\n%ld %ld\n255\n", m->width, m->height);
     if (!fwrite(m->data, m->width * m->height, 3, f))
         exit(EXIT_FAILURE);
 }
 
-static struct ppm *
-ppm_read(const char *filename)
+static struct ppm *ppm_read(const char *filename)
 {
     FILE *f = fopen(filename, "rb");
     if (f == NULL)
@@ -47,7 +44,10 @@ ppm_read(const char *filename)
     struct ppm *m;
     long width, height;
     if (fscanf(f, "P6 %ld%ld%*d%*c", &width, &height) < 2)
+    {
+        fprintf(stderr, "Not a valid PPM image.\n");
         return NULL;
+    }
     m = ppm_create(width, height);
     fread(m->data, width * height, 3, f);
     fclose(f);
@@ -115,7 +115,7 @@ int main(int argc, char **argv)
 
     error = imageSynth(&source_buffer, &mask_buffer, T_RGB, &params, NULL, NULL, &cancel_token);
 
-    if (error != 0)
+    if (error != IMAGE_SYNTH_SUCCESS)
         fprintf(stderr, "Operation failed. Error code: %d\n", error);
 
     FILE *result_file = fopen(result_out, "wb");