poppler/poppler-0.12.3-rotated-downscale.patch

60 lines
1.7 KiB
Diff

diff --git a/poppler/CairoOutputDev.cc b/poppler/CairoOutputDev.cc
index 5ca86b8..a2a9ae5 100644
--- a/poppler/CairoOutputDev.cc
+++ b/poppler/CairoOutputDev.cc
@@ -1344,6 +1344,30 @@ void CairoOutputDev::endMaskClip(GfxState *state) {
clearSoftMask(state);
}
+/* Taken from cairo/doc/tutorial/src/singular.c */
+static void
+get_singular_values (const cairo_matrix_t *matrix,
+ double *major,
+ double *minor)
+{
+ double xx = matrix->xx, xy = matrix->xy;
+ double yx = matrix->yx, yy = matrix->yy;
+
+ double a = xx*xx+yx*yx;
+ double b = xy*xy+yy*yy;
+ double k = xx*xy+yx*yy;
+
+ double f = (a+b) * .5;
+ double g = (a-b) * .5;
+ double delta = sqrt (g*g + k*k);
+
+ if (major)
+ *major = sqrt (f + delta);
+ if (minor)
+ *minor = sqrt (f - delta);
+}
+
+
cairo_surface_t *CairoOutputDev::downscaleSurface(cairo_surface_t *orig_surface) {
cairo_surface_t *dest_surface;
unsigned char *dest_buffer;
@@ -1356,12 +1380,21 @@ cairo_surface_t *CairoOutputDev::downscaleSurface(cairo_surface_t *orig_surface)
if (printing)
return NULL;
+
+ orig_width = cairo_image_surface_get_width (orig_surface);
+ orig_height = cairo_image_surface_get_height (orig_surface);
+
cairo_matrix_t matrix;
cairo_get_matrix(cairo, &matrix);
/* this whole computation should be factored out */
- double xScale = matrix.xx;
- double yScale = matrix.yy;
+ double xScale;
+ double yScale;
+ if (orig_width > orig_height)
+ get_singular_values (&matrix, &xScale, &yScale);
+ else
+ get_singular_values (&matrix, &yScale, &xScale);
+
int tx, tx2, ty, ty2; /* the integer co-oridinates of the resulting image */
int scaledHeight;
int scaledWidth;