sna/gen4: Hook in the poor-man's linear gradient

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 128 insertions, 2 deletions

diff --git a/src/sna/gen4_render.c b/src/sna/gen4_render.c
index 97af7fc9..404e12b0 100644
--- a/src/sna/gen4_render.c
+++ b/src/sna/gen4_render.c
@@ -1816,6 +1816,120 @@ gen4_composite_solid_init(struct sna *sna,
 	return channel->bo != NULL;
 }
 
+static Bool
+gen4_composite_linear_init(struct sna *sna,
+			   PicturePtr picture,
+			   struct sna_composite_channel *channel,
+			   int x, int y,
+			   int w, int h,
+			   int dst_x, int dst_y)
+{
+	PictLinearGradient *linear =
+		(PictLinearGradient *)picture->pSourcePict;
+	pixman_fixed_t tx, ty;
+	float x0, y0, sf;
+	float dx, dy;
+
+	DBG(("%s: p1=(%f, %f), p2=(%f, %f), src=(%d, %d), dst=(%d, %d), size=(%d, %d)\n",
+	     __FUNCTION__,
+	     pixman_fixed_to_double(linear->p1.x), pixman_fixed_to_double(linear->p1.y),
+	     pixman_fixed_to_double(linear->p2.x), pixman_fixed_to_double(linear->p2.y),
+	     x, y, dst_x, dst_y, w, h));
+
+	if (linear->p2.x == linear->p1.x && linear->p2.y == linear->p1.y)
+		return 0;
+
+	if (!sna_transform_is_affine(picture->transform)) {
+		DBG(("%s: fallback due to projective transform\n",
+		     __FUNCTION__));
+		return sna_render_picture_fixup(sna, picture, channel,
+						x, y, w, h, dst_x, dst_y);
+	}
+
+	channel->bo = sna_render_get_gradient(sna, (PictGradient *)linear);
+	if (!channel->bo)
+		return 0;
+
+	channel->filter = PictFilterBilinear;
+	channel->repeat = picture->repeat ? picture->repeatType : RepeatNone;
+	channel->width  = channel->bo->pitch / 4;
+	channel->height = 1;
+	channel->pict_format = PICT_a8r8g8b8;
+
+	channel->scale[0]  = channel->scale[1]  = 1;
+	channel->offset[0] = channel->offset[1] = 0;
+
+	if (sna_transform_is_translation(picture->transform, &tx, &ty)) {
+		dx = pixman_fixed_to_double(linear->p2.x - linear->p1.x);
+		dy = pixman_fixed_to_double(linear->p2.y - linear->p1.y);
+
+		x0 = pixman_fixed_to_double(linear->p1.x);
+		y0 = pixman_fixed_to_double(linear->p1.y);
+
+		if (tx | ty) {
+			x0 -= pixman_fixed_to_double(tx);
+			y0 -= pixman_fixed_to_double(ty);
+		}
+	} else {
+		struct pixman_f_vector p1, p2;
+		struct pixman_f_transform m, inv;
+
+		pixman_f_transform_from_pixman_transform(&m, picture->transform);
+		DBG(("%s: transform = [%f %f %f, %f %f %f, %f %f %f]\n",
+		     __FUNCTION__,
+		     m.m[0][0], m.m[0][1], m.m[0][2],
+		     m.m[1][0], m.m[1][1], m.m[1][2],
+		     m.m[2][0], m.m[2][1], m.m[2][2]));
+		if (!pixman_f_transform_invert(&inv, &m))
+			return 0;
+
+		p1.v[0] = pixman_fixed_to_double(linear->p1.x);
+		p1.v[1] = pixman_fixed_to_double(linear->p1.y);
+		p1.v[2] = 1.;
+		pixman_f_transform_point(&inv, &p1);
+
+		p2.v[0] = pixman_fixed_to_double(linear->p2.x);
+		p2.v[1] = pixman_fixed_to_double(linear->p2.y);
+		p2.v[2] = 1.;
+		pixman_f_transform_point(&inv, &p2);
+
+		DBG(("%s: untransformed: p1=(%f, %f, %f), p2=(%f, %f, %f)\n",
+		     __FUNCTION__,
+		     p1.v[0], p1.v[1], p1.v[2],
+		     p2.v[0], p2.v[1], p2.v[2]));
+
+		dx = p2.v[0] - p1.v[0];
+		dy = p2.v[1] - p1.v[1];
+
+		x0 = p1.v[0];
+		y0 = p1.v[1];
+	}
+
+	sf = dx*dx + dy*dy;
+	dx /= sf;
+	dy /= sf;
+
+	channel->embedded_transform.matrix[0][0] = pixman_double_to_fixed(dx);
+	channel->embedded_transform.matrix[0][1] = pixman_double_to_fixed(dy);
+	channel->embedded_transform.matrix[0][2] = -pixman_double_to_fixed(dx*(x0+dst_x-x) + dy*(y0+dst_y-y));
+
+	channel->embedded_transform.matrix[1][0] = 0;
+	channel->embedded_transform.matrix[1][1] = 0;
+	channel->embedded_transform.matrix[1][2] = pixman_double_to_fixed(.5);
+
+	channel->embedded_transform.matrix[2][0] = 0;
+	channel->embedded_transform.matrix[2][1] = 0;
+	channel->embedded_transform.matrix[2][2] = pixman_fixed_1;
+
+	channel->transform = &channel->embedded_transform;
+	channel->is_affine = 1;
+
+	DBG(("%s: dx=%f, dy=%f, offset=%f\n",
+	     __FUNCTION__, dx, dy, -dx*(x0-x+dst_x) + -dy*(y0-y+dst_y)));
+
+	return channel->bo != NULL;
+}
+
 static int
 gen4_composite_picture(struct sna *sna,
 		       PicturePtr picture,
@@ -1838,7 +1952,13 @@ gen4_composite_picture(struct sna *sna,
 		return gen4_composite_solid_init(sna, channel, color);
 
 	if (picture->pDrawable == NULL) {
-		DBG(("%s: procedural source fixup\n", __FUNCTION__));
+		if (picture->pSourcePict->type == SourcePictTypeLinear)
+			return gen4_composite_linear_init(sna, picture, channel,
+							  x, y,
+							  w, h,
+							  dst_x, dst_y);
+
+		DBG(("%s -- fixup, gradient\n", __FUNCTION__));
 		return sna_render_picture_fixup(sna, picture, channel,
 						x, y, w, h, dst_x, dst_y);
 	}
@@ -2004,7 +2124,13 @@ is_gradient(PicturePtr picture)
 	if (picture->pDrawable)
 		return FALSE;
 
-	return picture->pSourcePict->type != SourcePictTypeSolidFill;
+	switch (picture->pSourcePict->type) {
+	case SourcePictTypeSolidFill:
+	case SourcePictTypeLinear:
+		return FALSE;
+	default:
+		return TRUE;
+	}
 }
 
 static bool