1 files changed, 117 insertions, 0 deletions
diff --git a/tests/OffscreenContextWGL.cc b/tests/OffscreenContextWGL.cc
new file mode 100644
index 0000000..7f3703d
--- /dev/null
+++ b/tests/OffscreenContextWGL.cc
@@ -0,0 +1,117 @@
+/*
+
+Create an OpenGL context without creating an OpenGL Window. for Windows.
+
+*/
+
+#include "OffscreenContext.h"
+#include "printutils.h"
+#include "imageutils.h"
+#include "fbo.h"
+#include <vector>
+#include <GL/gl.h>
+
+using namespace std;
+
+struct OffscreenContext
+{
+//  GLXContext openGLContext;
+  int width;
+  int height;
+  fbo_t *fbo;
+};
+
+void offscreen_context_init(OffscreenContext &ctx, int width, int height)
+{
+  ctx.width = width;
+  ctx.height = height;
+  ctx.fbo = NULL;
+}
+
+
+void glewCheck() {
+#ifdef DEBUG
+  cerr << "GLEW version " << glewGetString(GLEW_VERSION) << "\n";
+  cerr << (const char *)glGetString(GL_RENDERER) << "(" << (const char *)glGetString(GL_VENDOR) << ")\n"
+       << "OpenGL version " << (const char *)glGetString(GL_VERSION) << "\n";
+  cerr  << "Extensions: " << (const char *)glGetString(GL_EXTENSIONS) << "\n";
+
+  if (GLEW_ARB_framebuffer_object) {
+    cerr << "ARB_FBO supported\n";
+  }
+  if (GLEW_EXT_framebuffer_object) {
+    cerr << "EXT_FBO supported\n";
+  }
+  if (GLEW_EXT_packed_depth_stencil) {
+    cerr << "EXT_packed_depth_stencil\n";
+  }
+#endif
+}
+
+OffscreenContext *create_offscreen_context(int w, int h)
+{
+  OffscreenContext *ctx = new OffscreenContext;
+  offscreen_context_init( *ctx, w, h );
+
+  // before an FBO can be setup, a GLX context must be created
+  // this call alters ctx->xDisplay and ctx->openGLContext 
+  //  and ctx->xwindow if successfull
+  cerr << "WGL not implemented\n";
+/*
+  if (!create_glx_dummy_context( *ctx )) {
+    return NULL;
+  }
+
+  glewInit(); //must come after Context creation and before FBO calls.
+  glewCheck();
+
+  ctx->fbo = fbo_new();
+  if (!fbo_init(ctx->fbo, w, h)) {
+    return NULL;
+  }
+
+*/
+  ctx = NULL;
+  return ctx;
+}
+
+bool teardown_offscreen_context(OffscreenContext *ctx)
+{
+  if (ctx) {
+    fbo_unbind(ctx->fbo);
+    fbo_delete(ctx->fbo);
+    return true;
+  }
+  return false;
+}
+
+/*!
+  Capture framebuffer from OpenGL and write it to the given filename as PNG.
+*/
+bool save_framebuffer(OffscreenContext *ctx, const char *filename)
+{
+  if (!ctx || !filename) return false;
+  int samplesPerPixel = 4; // R, G, B and A
+  vector<GLubyte> pixels(ctx->width * ctx->height * samplesPerPixel);
+  glReadPixels(0, 0, ctx->width, ctx->height, GL_RGBA, GL_UNSIGNED_BYTE, &pixels[0]);
+
+  // Flip it vertically - images read from OpenGL buffers are upside-down
+  int rowBytes = samplesPerPixel * ctx->width;
+  unsigned char *flippedBuffer = (unsigned char *)malloc(rowBytes * ctx->height);
+  if (!flippedBuffer) {
+    std::cerr << "Unable to allocate flipped buffer for corrected image.";
+    return 1;
+  }
+  flip_image(&pixels[0], flippedBuffer, samplesPerPixel, ctx->width, ctx->height);
+
+  bool writeok = write_png(filename, flippedBuffer, ctx->width, ctx->height);
+
+  free(flippedBuffer);
+
+  return writeok;
+}
+
+void bind_offscreen_context(OffscreenContext *ctx)
+{
+  if (ctx) fbo_bind(ctx->fbo);
+}