Giant commit!

A full detailed description of this will be done later... is several days
of work. Here's a summary:

Render:
- Full cleanup of render code, removing *all* globals and bad level calls
  all over blender. Render module is now not called abusive anymore
- API-fied calls to rendering
- Full recode of internal render pipeline. Is now rendering tiles by
  default, prepared for much smarter 'bucket' render later.
- Each thread now can render a full part
- Renders were tested with 4 threads, goes fine, apart from some lookup
  tables in softshadow and AO still
- Rendering is prepared to do multiple layers and passes
- No single 32 bits trick in render code anymore, all 100% floats now.

Writing images/movies
- moved writing images to blender kernel (bye bye 'schrijfplaatje'!)
- made a new Movie handle system, also in kernel. This will enable much
  easier use of movies in Blender

PreviewRender:
- Using new render API, previewrender (in buttons) now uses regular render
  code to generate images.
- new datafile 'preview.blend.c' has the preview scenes in it
- previews get rendered in exact displayed size (1 pixel = 1 pixel)

3D Preview render
- new; press Pkey in 3d window, for a panel that continuously renders
  (pkey is for games, i know... but we dont do that in orange now!)
- this render works nearly identical to buttons-preview render, so it stops
  rendering on any event (mouse, keyboard, etc)
- on moving/scaling the panel, the render code doesn't recreate all geometry
- same for shifting/panning view
- all other operations (now) regenerate the full render database still.
- this is WIP... but big fun, especially for simple scenes!

Compositor
- Using same node system as now in use for shaders, you can composit images
- works pretty straightforward... needs much more options/tools and integration
  with rendering still
- is not threaded yet, nor is so smart to only recalculate changes... will be
  done soon!
- the "Render Result" node will get all layers/passes as output sockets
- The "Output" node renders to a builtin image, which you can view in the Image
  window. (yes, output nodes to render-result, and to files, is on the list!)

The Bad News
- "Unified Render" is removed. It might come back in some stage, but this
  system should be built from scratch. I can't really understand this code...
  I expect it is not much needed, especially with advanced layer/passes
  control
- Panorama render, Field render, Motion blur, is not coded yet... (I had to
  recode every single feature in render, so...!)
- Lens Flare is also not back... needs total revision, might become composit
  effect though (using zbuffer for visibility)
- Part render is gone! (well, thats obvious, its default now).
- The render window is only restored with limited functionality... I am going
  to check first the option to render to a Image window, so Blender can become
  a true single-window application. :)
  For example, the 'Spare render buffer' (jkey) doesnt work.
- Render with border, now default creates a smaller image
- No zbuffers are written yet... on the todo!
- Scons files and MSVC will need work to get compiling again

OK... thats what I can quickly recall. Now go compiling!

source/blender/src/glutil.c

@@ -286,7 +286,7 @@ void glaDrawPixelsTex(float x, float y, int img_w, int img_h, int format, void *
 	glPixelStorei(GL_UNPACK_ROW_LENGTH, lrowlength);
 }
 
-void glaDrawPixelsSafe(float x, float y, int img_w, int img_h, int format, int type, void *rect)
+void glaDrawPixelsSafe(float x, float y, int img_w, int img_h, int row_w, int format, int type, void *rect)
 {
 	float xzoom= glaGetOneFloat(GL_ZOOM_X);
 	float yzoom= glaGetOneFloat(GL_ZOOM_Y);
@@ -338,25 +338,25 @@ void glaDrawPixelsSafe(float x, float y, int img_w, int img_h, int format, int t
 			glaRasterPosSafe2f(rast_x, rast_y, 0, 0);
 		}
 
-		glPixelStorei(GL_UNPACK_ROW_LENGTH, img_w);
+		glPixelStorei(GL_UNPACK_ROW_LENGTH, row_w);
 		if(format==GL_LUMINANCE || format==GL_RED) {
 			if(type==GL_FLOAT) {
 				float *f_rect= (float *)rect;
-				glDrawPixels(draw_w, draw_h, format, type, f_rect + (off_y*img_w + off_x));
+				glDrawPixels(draw_w, draw_h, format, type, f_rect + (off_y*row_w + off_x));
 			}
 			else if(type==GL_INT || type==GL_UNSIGNED_INT) {
 				int *i_rect= (int *)rect;
-				glDrawPixels(draw_w, draw_h, format, type, i_rect + (off_y*img_w + off_x));
+				glDrawPixels(draw_w, draw_h, format, type, i_rect + (off_y*row_w + off_x));
 			}
 		}
 		else { /* RGBA */
 			if(type==GL_FLOAT) {
 				float *f_rect= (float *)rect;
-				glDrawPixels(draw_w, draw_h, format, type, f_rect + (off_y*img_w + off_x)*4);
+				glDrawPixels(draw_w, draw_h, format, type, f_rect + (off_y*row_w + off_x)*4);
 			}
 			else if(type==GL_UNSIGNED_BYTE) {
 				unsigned char *uc_rect= (unsigned char *) rect;
-				glDrawPixels(draw_w, draw_h, format, type, uc_rect + (off_y*img_w + off_x)*4);
+				glDrawPixels(draw_w, draw_h, format, type, uc_rect + (off_y*row_w + off_x)*4);
 			}
 		}