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diff --git a/Build/source/libs/libpng/libpng-src/contrib/examples/simpleover.c b/Build/source/libs/libpng/libpng-src/contrib/examples/simpleover.c
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+/*- simpleover
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2015.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work. This work is published from:
+ * United States.
+ *
+ * Read several PNG files, which should have an alpha channel or transparency
+ * information, and composite them together to produce one or more 16-bit linear
+ * RGBA intermediates. This involves doing the correct 'over' composition to
+ * combine the alpha channels and corresponding data.
+ *
+ * Finally read an output (background) PNG using the 24-bit RGB format (the
+ * PNG will be composited on green (#00ff00) by default if it has an alpha
+ * channel), and apply the intermediate image generated above to specified
+ * locations in the image.
+ *
+ * The command line has the general format:
+ *
+ * simpleover <background.png> [output.png]
+ * {--sprite=width,height,name {[--at=x,y] {sprite.png}}}
+ * {--add=name {x,y}}
+ *
+ * The --sprite and --add options may occur multiple times. They are executed
+ * in order. --add may refer to any sprite already read.
+ *
+ * This code is intended to show how to composite multiple images together
+ * correctly. Apart from the libpng Simplified API the only work done in here
+ * is to combine multiple input PNG images into a single sprite; this involves
+ * a Porter-Duff 'over' operation and the input PNG images may, as a result,
+ * be regarded as being layered one on top of the other with the first (leftmost
+ * on the command line) being at the bottom and the last on the top.
+ */
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+
+/* Normally use <png.h> here to get the installed libpng, but this is done to
+ * ensure the code picks up the local libpng implementation, so long as this
+ * file is linked against a sufficiently recent libpng (1.6+) it is ok to
+ * change this to <png.h>:
+ */
+#include "../../png.h"
+
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+
+#define sprite_name_chars 15
+struct sprite {
+ FILE *file;
+ png_uint_16p buffer;
+ unsigned int width;
+ unsigned int height;
+ char name[sprite_name_chars+1];
+};
+
+#if 0 /* div by 65535 test program */
+#include <math.h>
+#include <stdio.h>
+
+int main(void) {
+ double err = 0;
+ unsigned int xerr = 0;
+ unsigned int r = 32769;
+ {
+ unsigned int x = 0;
+
+ do {
+ unsigned int t = x + (x >> 16) /*+ (x >> 31)*/ + r;
+ double v = x, errtest;
+
+ if (t < x) {
+ fprintf(stderr, "overflow: %u+%u -> %u\n", x, r, t);
+ return 1;
+ }
+
+ v /= 65535;
+ errtest = v;
+ t >>= 16;
+ errtest -= t;
+
+ if (errtest > err) {
+ err = errtest;
+ xerr = x;
+
+ if (errtest >= .5) {
+ fprintf(stderr, "error: %u/65535 = %f, not %u, error %f\n",
+ x, v, t, errtest);
+ return 0;
+ }
+ }
+ } while (++x <= 65535U*65535U);
+ }
+
+ printf("error %f @ %u\n", err, xerr);
+
+ return 0;
+}
+#endif /* div by 65535 test program */
+
+static void
+sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
+ png_imagep image, const png_uint_16 *buffer)
+{
+ /* This is where the Porter-Duff 'Over' operator is evaluated; change this
+ * code to change the operator (this could be parameterized). Any other
+ * image processing operation could be used here.
+ */
+
+
+ /* Check for an x or y offset that pushes any part of the image beyond the
+ * right or bottom of the sprite:
+ */
+ if ((y_offset < 0 || (unsigned)/*SAFE*/y_offset < sprite->height) &&
+ (x_offset < 0 || (unsigned)/*SAFE*/x_offset < sprite->width))
+ {
+ unsigned int y = 0;
+
+ if (y_offset < 0)
+ y = -y_offset; /* Skip to first visible row */
+
+ do
+ {
+ unsigned int x = 0;
+
+ if (x_offset < 0)
+ x = -x_offset;
+
+ do
+ {
+ /* In and out are RGBA values, so: */
+ const png_uint_16 *in_pixel = buffer + (y * image->width + x)*4;
+ png_uint_32 in_alpha = in_pixel[3];
+
+ /* This is the optimized Porter-Duff 'Over' operation, when the
+ * input alpha is 0 the output is not changed.
+ */
+ if (in_alpha > 0)
+ {
+ png_uint_16 *out_pixel = sprite->buffer +
+ ((y+y_offset) * sprite->width + (x+x_offset))*4;
+
+ /* This is the weight to apply to the output: */
+ in_alpha = 65535-in_alpha;
+
+ if (in_alpha > 0)
+ {
+ /* The input must be composed onto the output. This means
+ * multiplying the current output pixel value by the inverse
+ * of the input alpha (1-alpha). A division is required but
+ * it is by the constant 65535. Approximate this as:
+ *
+ * (x + (x >> 16) + 32769) >> 16;
+ *
+ * This is exact (and does not overflow) for all values of
+ * x in the range 0..65535*65535. (Note that the calculation
+ * produces the closest integer; the maximum error is <0.5).
+ */
+ png_uint_32 tmp;
+
+# define compose(c)\
+ tmp = out_pixel[c] * in_alpha;\
+ tmp = (tmp + (tmp >> 16) + 32769) >> 16;\
+ out_pixel[c] = tmp + in_pixel[c]
+
+ /* The following is very vectorizable... */
+ compose(0);
+ compose(1);
+ compose(2);
+ compose(3);
+ }
+
+ else
+ out_pixel[0] = in_pixel[0],
+ out_pixel[1] = in_pixel[1],
+ out_pixel[2] = in_pixel[2],
+ out_pixel[3] = in_pixel[3];
+ }
+ }
+ while (++x < image->width);
+ }
+ while (++y < image->height);
+ }
+}
+
+static int
+create_sprite(struct sprite *sprite, int *argc, const char ***argv)
+{
+ /* Read the arguments and create this sprite. The sprite buffer has already
+ * been allocated. This reads the input PNGs one by one in linear format,
+ * composes them onto the sprite buffer (the code in the function above)
+ * then saves the result, converting it on the fly to PNG RGBA 8-bit format.
+ */
+ while (*argc > 0)
+ {
+ char tombstone;
+ int x = 0, y = 0;
+
+ if ((*argv)[0][0] == '-' && (*argv)[0][1] == '-')
+ {
+ /* The only supported option is --at. */
+ if (sscanf((*argv)[0], "--at=%d,%d%c", &x, &y, &tombstone) != 2)
+ break; /* success; caller will parse this option */
+
+ ++*argv, --*argc;
+ }
+
+ else
+ {
+ /* The argument has to be a file name */
+ png_image image;
+
+ image.version = PNG_IMAGE_VERSION;
+ image.opaque = NULL;
+
+ if (png_image_begin_read_from_file(&image, (*argv)[0]))
+ {
+ png_uint_16p buffer;
+
+ image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+
+ buffer = malloc(PNG_IMAGE_SIZE(image));
+
+ if (buffer != NULL)
+ {
+ if (png_image_finish_read(&image, NULL/*background*/, buffer,
+ 0/*row_stride*/,
+ NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
+ {
+ /* This is the place where the Porter-Duff 'Over' operator
+ * needs to be done by this code. In fact, any image
+ * processing required can be done here; the data is in
+ * the correct format (linear, 16-bit) and source and
+ * destination are in memory.
+ */
+ sprite_op(sprite, x, y, &image, buffer);
+ free(buffer);
+ ++*argv, --*argc;
+ /* And continue to the next argument */
+ continue;
+ }
+
+ else
+ {
+ free(buffer);
+ fprintf(stderr, "simpleover: read %s: %s\n", (*argv)[0],
+ image.message);
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
+ (unsigned long)PNG_IMAGE_SIZE(image));
+
+ /* png_image_free must be called if we abort the Simplified API
+ * read because of a problem detected in this code. If problems
+ * are detected in the Simplified API it cleans up itself.
+ */
+ png_image_free(&image);
+ }
+ }
+
+ else
+ {
+ /* Failed to read the first argument: */
+ fprintf(stderr, "simpleover: %s: %s\n", (*argv)[0], image.message);
+ }
+
+ return 0; /* failure */
+ }
+ }
+
+ /* All the sprite operations have completed successfully. Save the RGBA
+ * buffer as a PNG using the simplified write API.
+ */
+ sprite->file = tmpfile();
+
+ if (sprite->file != NULL)
+ {
+ png_image save;
+
+ memset(&save, 0, sizeof save);
+ save.version = PNG_IMAGE_VERSION;
+ save.opaque = NULL;
+ save.width = sprite->width;
+ save.height = sprite->height;
+ save.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+ save.flags = PNG_IMAGE_FLAG_FAST;
+ save.colormap_entries = 0;
+
+ if (png_image_write_to_stdio(&save, sprite->file, 1/*convert_to_8_bit*/,
+ sprite->buffer, 0/*row_stride*/, NULL/*colormap*/))
+ {
+ /* Success; the buffer is no longer needed: */
+ free(sprite->buffer);
+ sprite->buffer = NULL;
+ return 1; /* ok */
+ }
+
+ else
+ fprintf(stderr, "simpleover: write sprite %s: %s\n", sprite->name,
+ save.message);
+ }
+
+ else
+ fprintf(stderr, "simpleover: sprite %s: could not allocate tmpfile: %s\n",
+ sprite->name, strerror(errno));
+
+ return 0; /* fail */
+}
+
+static int
+add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
+ int *argc, const char ***argv)
+{
+ /* Given a --add argument naming this sprite, perform the operations listed
+ * in the following arguments. The arguments are expected to have the form
+ * (x,y), which is just an offset at which to add the sprite to the
+ * output.
+ */
+ while (*argc > 0)
+ {
+ char tombstone;
+ int x, y;
+
+ if ((*argv)[0][0] == '-' && (*argv)[0][1] == '-')
+ return 1; /* success */
+
+ if (sscanf((*argv)[0], "%d,%d%c", &x, &y, &tombstone) == 2)
+ {
+ /* Now add the new image into the sprite data, but only if it
+ * will fit.
+ */
+ if (x < 0 || y < 0 ||
+ (unsigned)/*SAFE*/x >= output->width ||
+ (unsigned)/*SAFE*/y >= output->height ||
+ sprite->width > output->width-x ||
+ sprite->height > output->height-y)
+ {
+ fprintf(stderr, "simpleover: sprite %s @ (%d,%d) outside image\n",
+ sprite->name, x, y);
+ /* Could just skip this, but for the moment it is an error */
+ return 0; /* error */
+ }
+
+ else
+ {
+ /* Since we know the sprite fits we can just read it into the
+ * output using the simplified API.
+ */
+ png_image in;
+
+ in.version = PNG_IMAGE_VERSION;
+ rewind(sprite->file);
+
+ if (png_image_begin_read_from_stdio(&in, sprite->file))
+ {
+ in.format = PNG_FORMAT_RGB; /* force compose */
+
+ if (png_image_finish_read(&in, NULL/*background*/,
+ out_buf + (y*output->width + x)*3/*RGB*/,
+ output->width*3/*row_stride*/,
+ NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
+ {
+ ++*argv, --*argc;
+ continue;
+ }
+ }
+
+ /* The read failed: */
+ fprintf(stderr, "simpleover: add sprite %s: %s\n", sprite->name,
+ in.message);
+ return 0; /* error */
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: --add='%s': invalid position %s\n",
+ sprite->name, (*argv)[0]);
+ return 0; /* error */
+ }
+ }
+
+ return 1; /* ok */
+}
+
+static int
+simpleover_process(png_imagep output, png_bytep out_buf, int argc,
+ const char **argv)
+{
+ int result = 1; /* success */
+# define csprites 10/*limit*/
+# define str(a) #a
+ int nsprites = 0;
+ struct sprite sprites[csprites];
+
+ while (argc > 0)
+ {
+ result = 0; /* fail */
+
+ if (strncmp(argv[0], "--sprite=", 9) == 0)
+ {
+ char tombstone;
+
+ if (nsprites < csprites)
+ {
+ int n;
+
+ sprites[nsprites].width = sprites[nsprites].height = 0;
+ sprites[nsprites].name[0] = 0;
+
+ n = sscanf(argv[0], "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
+ &sprites[nsprites].width, &sprites[nsprites].height,
+ sprites[nsprites].name, &tombstone);
+
+ if ((n == 2 || n == 3) &&
+ sprites[nsprites].width > 0 && sprites[nsprites].height > 0)
+ {
+ size_t buf_size, tmp;
+
+ /* Default a name if not given. */
+ if (sprites[nsprites].name[0] == 0)
+ sprintf(sprites[nsprites].name, "sprite-%d", nsprites+1);
+
+ /* Allocate a buffer for the sprite and calculate the buffer
+ * size:
+ */
+ buf_size = sizeof (png_uint_16 [4]);
+ buf_size *= sprites[nsprites].width;
+ buf_size *= sprites[nsprites].height;
+
+ /* This can overflow a (size_t); check for this: */
+ tmp = buf_size;
+ tmp /= sprites[nsprites].width;
+ tmp /= sprites[nsprites].height;
+
+ if (tmp == sizeof (png_uint_16 [4]))
+ {
+ sprites[nsprites].buffer = malloc(buf_size);
+ /* This buffer must be initialized to transparent: */
+ memset(sprites[nsprites].buffer, 0, buf_size);
+
+ if (sprites[nsprites].buffer != NULL)
+ {
+ sprites[nsprites].file = NULL;
+ ++argv, --argc;
+
+ if (create_sprite(sprites+nsprites++, &argc, &argv))
+ {
+ result = 1; /* still ok */
+ continue;
+ }
+
+ break; /* error */
+ }
+ }
+
+ /* Overflow, or OOM */
+ fprintf(stderr, "simpleover: %s: sprite too large\n", argv[0]);
+ break;
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: %s: invalid sprite (%u,%u)\n",
+ argv[0], sprites[nsprites].width, sprites[nsprites].height);
+ break;
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: %s: too many sprites\n", argv[0]);
+ break;
+ }
+ }
+
+ else if (strncmp(argv[0], "--add=", 6) == 0)
+ {
+ const char *name = argv[0]+6;
+ int isprite = nsprites;
+
+ ++argv, --argc;
+
+ while (--isprite >= 0)
+ {
+ if (strcmp(sprites[isprite].name, name) == 0)
+ {
+ if (!add_sprite(output, out_buf, sprites+isprite, &argc, &argv))
+ goto out; /* error in add_sprite */
+
+ break;
+ }
+ }
+
+ if (isprite < 0) /* sprite not found */
+ {
+ fprintf(stderr, "simpleover: --add='%s': sprite not found\n", name);
+ break;
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: %s: unrecognized operation\n", argv[0]);
+ break;
+ }
+
+ result = 1; /* ok */
+ }
+
+ /* Clean up the cache of sprites: */
+out:
+ while (--nsprites >= 0)
+ {
+ if (sprites[nsprites].buffer != NULL)
+ free(sprites[nsprites].buffer);
+
+ if (sprites[nsprites].file != NULL)
+ (void)fclose(sprites[nsprites].file);
+ }
+
+ return result;
+}
+
+int main(int argc, const char **argv)
+{
+ int result = 1; /* default to fail */
+
+ if (argc >= 2)
+ {
+ int argi = 2;
+ const char *output = NULL;
+ png_image image;
+
+ if (argc > 2 && argv[2][0] != '-'/*an operation*/)
+ {
+ output = argv[2];
+ argi = 3;
+ }
+
+ image.version = PNG_IMAGE_VERSION;
+ image.opaque = NULL;
+
+ if (png_image_begin_read_from_file(&image, argv[1]))
+ {
+ png_bytep buffer;
+
+ image.format = PNG_FORMAT_RGB; /* 24-bit RGB */
+
+ buffer = malloc(PNG_IMAGE_SIZE(image));
+
+ if (buffer != NULL)
+ {
+ png_color background = {0, 0xff, 0}; /* fully saturated green */
+
+ if (png_image_finish_read(&image, &background, buffer,
+ 0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
+ {
+ /* At this point png_image_finish_read has cleaned up the
+ * allocated data in png_image, and only the buffer needs to be
+ * freed.
+ *
+ * Perform the remaining operations:
+ */
+ if (simpleover_process(&image, buffer, argc-argi, argv+argi))
+ {
+ /* Write the output: */
+ if ((output != NULL &&
+ png_image_write_to_file(&image, output,
+ 0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
+ NULL/*colormap*/)) ||
+ (output == NULL &&
+ png_image_write_to_stdio(&image, stdout,
+ 0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
+ NULL/*colormap*/)))
+ result = 0;
+
+ else
+ fprintf(stderr, "simpleover: write %s: %s\n",
+ output == NULL ? "stdout" : output, image.message);
+ }
+
+ /* else simpleover_process writes an error message */
+ }
+
+ else
+ fprintf(stderr, "simpleover: read %s: %s\n", argv[1],
+ image.message);
+
+ free(buffer);
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
+ (unsigned long)PNG_IMAGE_SIZE(image));
+
+ /* This is the only place where a 'free' is required; libpng does
+ * the cleanup on error and success, but in this case we couldn't
+ * complete the read because of running out of memory.
+ */
+ png_image_free(&image);
+ }
+ }
+
+ else
+ {
+ /* Failed to read the first argument: */
+ fprintf(stderr, "simpleover: %s: %s\n", argv[1], image.message);
+ }
+ }
+
+ else
+ {
+ /* Usage message */
+ fprintf(stderr,
+ "simpleover: usage: simpleover background.png [output.png]\n"
+ " Output 'background.png' as a 24-bit RGB PNG file in 'output.png'\n"
+ " or, if not given, stdout. 'background.png' will be composited\n"
+ " on fully saturated green.\n"
+ "\n"
+ " Optionally, before output, process additional PNG files:\n"
+ "\n"
+ " --sprite=width,height,name {[--at=x,y] {sprite.png}}\n"
+ " Produce a transparent sprite of size (width,height) and with\n"
+ " name 'name'.\n"
+ " For each sprite.png composite it using a Porter-Duff 'Over'\n"
+ " operation at offset (x,y) in the sprite (defaulting to (0,0)).\n"
+ " Input PNGs will be truncated to the area of the sprite.\n"
+ "\n"
+ " --add='name' {x,y}\n"
+ " Optionally, before output, composite a sprite, 'name', which\n"
+ " must have been previously produced using --sprite, at each\n"
+ " offset (x,y) in the output image. Each sprite must fit\n"
+ " completely within the output image.\n"
+ "\n"
+ " PNG files are processed in the order they occur on the command\n"
+ " line and thus the first PNG processed appears as the bottommost\n"
+ " in the output image.\n");
+ }
+
+ return result;
+}
+#endif /* SIMPLIFIED_READ */