1 files changed, 80 insertions, 0 deletions
diff --git a/src/glut/glx/glut_ppm.c b/src/glut/glx/glut_ppm.c
new file mode 100644
index 00000000000..49dca8532fd
--- /dev/null
+++ b/src/glut/glx/glut_ppm.c
@@ -0,0 +1,80 @@
+/*
+ * PPM file output
+ * Brian Paul
+ * 8 Dec 2008
+ */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "glutint.h"
+
+
+static void
+write_ppm_file(const char *filename, const GLubyte *buffer,
+               int width, int height)
+{
+   const int binary = 1;
+   FILE *f = fopen( filename, "w" );
+   if (f) {
+      const GLubyte *ptr = buffer;
+      int i, x, y;
+      if (binary) {
+         fprintf(f,"P6\n");
+         fprintf(f,"# ppm-file created by GLUT\n");
+         fprintf(f,"%i %i\n", width, height);
+         fprintf(f,"255\n");
+         fclose(f);
+         f = fopen( filename, "ab" );  /* reopen in binary append mode */
+         for (y = height - 1; y >= 0; y--) {
+            for (x = 0; x < width; x++) {
+               i = (y * width + x) * 4;
+               fputc(ptr[i], f);   /* write red */
+               fputc(ptr[i+1], f); /* write green */
+               fputc(ptr[i+2], f); /* write blue */
+            }
+         }
+      }
+      else {
+         /*ASCII*/
+         int counter = 0;
+         fprintf(f,"P3\n");
+         fprintf(f,"# ascii ppm file created by GLUT\n");
+         fprintf(f,"%i %i\n", width, height);
+         fprintf(f,"255\n");
+         for (y = height - 1; y >= 0; y--) {
+            for (x = 0; x < width; x++) {
+               i = (y * width + x) * 4;
+               fprintf(f, " %3d %3d %3d", ptr[i], ptr[i+1], ptr[i+2]);
+               counter++;
+               if (counter % 5 == 0)
+                  fprintf(f, "\n");
+            }
+         }
+      }
+      fclose(f);
+   }
+}
+
+
+/**
+ * Called from SwapBuffers if the GLUT_PPM_FILE env var is set.
+ */
+void __glutWritePPMFile(void)
+{
+   int w = glutGet(GLUT_WINDOW_WIDTH);
+   int h = glutGet(GLUT_WINDOW_HEIGHT);
+   GLubyte *buf;
+
+   assert(__glutPPMFile);
+
+   buf = (GLubyte *) malloc(w * h * 4);
+   if (buf) {
+      /* XXX save/restore pixel packing */
+      glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, buf);
+      write_ppm_file(__glutPPMFile, buf, w, h);
+      free(buf);
+   }
+
+   __glutPPMFile = NULL; /* only write one file */
+}