Check return value from SDL_Init().
[movit] / demo.cpp
index 5fec3fc..6e5f18c 100644 (file)
--- a/demo.cpp
+++ b/demo.cpp
@@ -19,6 +19,7 @@
 #include <SDL/SDL.h>
 #include <SDL/SDL_opengl.h>
 #include <SDL/SDL_image.h>
+#include <png.h>
 
 #include "init.h"
 #include "effect.h"
@@ -129,26 +130,43 @@ unsigned char *load_image(const char *filename, unsigned *w, unsigned *h)
        return (unsigned char *)converted->pixels;
 }
 
-void write_ppm(const char *filename, unsigned char *screenbuf)
+void write_png(const char *filename, unsigned char *screenbuf)
 {
-       FILE *fp = fopen(filename, "w");
-       fprintf(fp, "P6\n%d %d\n255\n", WIDTH, HEIGHT);
+       FILE *fp = fopen(filename, "wb");
+       png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+       png_infop info_ptr = png_create_info_struct(png_ptr);
+       
+       if (setjmp(png_jmpbuf(png_ptr))) {
+               fclose(fp);
+               fprintf(stderr, "Write to %s failed; exiting.\n", filename);
+               exit(1);
+       }
+
+       png_set_IHDR(png_ptr, info_ptr, WIDTH, HEIGHT, 8, PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+       png_bytep *row_pointers = new png_bytep[HEIGHT];
        for (unsigned y = 0; y < HEIGHT; ++y) {
-               unsigned char *srcptr = screenbuf + ((HEIGHT - y - 1) * WIDTH) * 4;
-               for (unsigned x = 0; x < WIDTH; ++x) {
-                       fputc(srcptr[x * 4 + 2], fp);
-                       fputc(srcptr[x * 4 + 1], fp);
-                       fputc(srcptr[x * 4 + 0], fp);
-               }
+               row_pointers[y] = screenbuf + ((HEIGHT - y - 1) * WIDTH) * 4;
        }
+
+       png_init_io(png_ptr, fp);
+       png_set_rows(png_ptr, info_ptr, row_pointers);
+       png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_BGR, NULL);
+       png_destroy_write_struct(&png_ptr, &info_ptr);
        fclose(fp);
+
+       delete[] row_pointers;
 }
 
 int main(int argc, char **argv)
 {
        bool quit = false;
 
-       SDL_Init(SDL_INIT_EVERYTHING);
+       if (SDL_Init(SDL_INIT_EVERYTHING) == -1) {
+               fprintf(stderr, "SDL_Init failed: %s\n", SDL_GetError());
+               exit(1);
+       }
+       SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);
        SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 0);
        SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0);
        SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
@@ -258,8 +276,8 @@ int main(int argc, char **argv)
                check_error();
                if (screenshot) {
                        char filename[256];
-                       sprintf(filename, "frame%05d.ppm", frame);
-                       write_ppm(filename, screenbuf);
+                       sprintf(filename, "frame%05d.png", frame);
+                       write_png(filename, screenbuf);
                        printf("Screenshot: %s\n", filename);
                        screenshot = false;
                }