From f08f46797df8d6cca982c08ed16eb1934b1dc7d9 Mon Sep 17 00:00:00 2001
From: Tor Andersson <tor.andersson@artifex.com>
Date: Fri, 20 Jan 2012 17:39:25 +0100
Subject: Flip images the right side up in the PDF interpreter.

This way both pixmaps for rendering and image data are top-down.
---
 draw/draw_affine.c  |  3 +--
 pdf/pdf_interpret.c | 17 +++++++++++------
 xps/xps_image.c     |  5 +----
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/draw/draw_affine.c b/draw/draw_affine.c
index a90ac087..dc15eaf5 100644
--- a/draw/draw_affine.c
+++ b/draw/draw_affine.c
@@ -647,8 +647,7 @@ fz_paint_image_imp(fz_pixmap *dst, fz_bbox scissor, fz_pixmap *shape, fz_pixmap
 	h -= y;
 
 	/* map from screen space (x,y) to image space (u,v) */
-	inv = fz_scale(1.0f / img->w, -1.0f / img->h);
-	inv = fz_concat(inv, fz_translate(0, 1));
+	inv = fz_scale(1.0f / img->w, 1.0f / img->h);
 	inv = fz_concat(inv, ctm);
 	inv = fz_invert_matrix(inv);
 
diff --git a/pdf/pdf_interpret.c b/pdf/pdf_interpret.c
index 9d9d2cfc..ff9a8f2c 100644
--- a/pdf/pdf_interpret.c
+++ b/pdf/pdf_interpret.c
@@ -364,19 +364,24 @@ static void
 pdf_show_image(pdf_csi *csi, fz_pixmap *image)
 {
 	pdf_gstate *gstate = csi->gstate + csi->gtop;
+	fz_matrix image_ctm;
 	fz_rect bbox;
 
 	if (csi->in_hidden_ocg > 0)
 		return;
 
-	bbox = fz_transform_rect(gstate->ctm, fz_unit_rect);
+	/* PDF has images bottom-up, so flip them right side up here */
+	image_ctm = fz_concat(fz_scale(1, -1), fz_translate(0, 1));
+	image_ctm = fz_concat(image_ctm, gstate->ctm);
+
+	bbox = fz_transform_rect(image_ctm, fz_unit_rect);
 
 	if (image->mask)
 	{
 		/* apply blend group even though we skip the softmask */
 		if (gstate->blendmode)
 			fz_begin_group(csi->dev, bbox, 0, 0, gstate->blendmode, 1);
-		fz_clip_image_mask(csi->dev, image->mask, &bbox, gstate->ctm);
+		fz_clip_image_mask(csi->dev, image->mask, &bbox, image_ctm);
 	}
 	else
 		pdf_begin_group(csi, bbox);
@@ -389,13 +394,13 @@ pdf_show_image(pdf_csi *csi, fz_pixmap *image)
 		case PDF_MAT_NONE:
 			break;
 		case PDF_MAT_COLOR:
-			fz_fill_image_mask(csi->dev, image, gstate->ctm,
+			fz_fill_image_mask(csi->dev, image, image_ctm,
 				gstate->fill.colorspace, gstate->fill.v, gstate->fill.alpha);
 			break;
 		case PDF_MAT_PATTERN:
 			if (gstate->fill.pattern)
 			{
-				fz_clip_image_mask(csi->dev, image, &bbox, gstate->ctm);
+				fz_clip_image_mask(csi->dev, image, &bbox, image_ctm);
 				pdf_show_pattern(csi, gstate->fill.pattern, bbox, PDF_FILL);
 				fz_pop_clip(csi->dev);
 			}
@@ -403,7 +408,7 @@ pdf_show_image(pdf_csi *csi, fz_pixmap *image)
 		case PDF_MAT_SHADE:
 			if (gstate->fill.shade)
 			{
-				fz_clip_image_mask(csi->dev, image, &bbox, gstate->ctm);
+				fz_clip_image_mask(csi->dev, image, &bbox, image_ctm);
 				fz_fill_shade(csi->dev, gstate->fill.shade, gstate->ctm, gstate->fill.alpha);
 				fz_pop_clip(csi->dev);
 			}
@@ -412,7 +417,7 @@ pdf_show_image(pdf_csi *csi, fz_pixmap *image)
 	}
 	else
 	{
-		fz_fill_image(csi->dev, image, gstate->ctm, gstate->fill.alpha);
+		fz_fill_image(csi->dev, image, image_ctm, gstate->fill.alpha);
 	}
 
 	if (image->mask)
diff --git a/xps/xps_image.c b/xps/xps_image.c
index 85a467af..6ba514b7 100644
--- a/xps/xps_image.c
+++ b/xps/xps_image.c
@@ -29,15 +29,12 @@ xps_paint_image_brush(xps_document *doc, fz_matrix ctm, fz_rect area, char *base
 {
 	fz_pixmap *pixmap = vimage;
 	float xs, ys;
-	fz_matrix im;
 
 	if (pixmap->xres == 0 || pixmap->yres == 0)
 		return;
 	xs = pixmap->w * 96 / pixmap->xres;
 	ys = pixmap->h * 96 / pixmap->yres;
-	im = fz_scale(xs, -ys);
-	im.f = ys;
-	ctm = fz_concat(im, ctm);
+	ctm = fz_concat(fz_scale(xs, ys), ctm);
 	fz_fill_image(doc->dev, pixmap, ctm, doc->opacity[doc->opacity_top]);
 }
 
-- 
cgit v1.2.3