From: Marc-André Lureau <marcandre.lureau@redhat.com>

Use a simpler implementation for rectangle geometry & intersect, drop
the need for (more complex) PIXMAN functions.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
---
 include/ui/rect.h       | 59 +++++++++++++++++++++++++++++++++++++++++
 hw/display/virtio-gpu.c | 30 ++++++++-------------
 2 files changed, 70 insertions(+), 19 deletions(-)
 create mode 100644 include/ui/rect.h

diff --git a/include/ui/rect.h b/include/ui/rect.h
new file mode 100644
index 0000000000..94898f92d0
--- /dev/null
+++ b/include/ui/rect.h
@@ -0,0 +1,59 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef QEMU_RECT_H
+#define QEMU_RECT_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+typedef struct QemuRect {
+    int16_t x;
+    int16_t y;
+    uint16_t width;
+    uint16_t height;
+} QemuRect;
+
+static inline void qemu_rect_init(QemuRect *rect,
+                                  int16_t x, int16_t y,
+                                  uint16_t width, uint16_t height)
+{
+    rect->x = x;
+    rect->y = x;
+    rect->width = width;
+    rect->height = height;
+}
+
+static inline void qemu_rect_translate(QemuRect *rect,
+                                       int16_t dx, int16_t dy)
+{
+    rect->x += dx;
+    rect->y += dy;
+}
+
+static inline bool qemu_rect_intersect(const QemuRect *a, const QemuRect *b,
+                                       QemuRect *res)
+{
+    int16_t x1, x2, y1, y2;
+
+    x1 = MAX(a->x, b->x);
+    y1 = MAX(a->y, b->y);
+    x2 = MIN(a->x + a->width, b->x + b->width);
+    y2 = MIN(a->y + a->height, b->y + b->height);
+
+    if (x1 >= x2 || y1 >= y2) {
+        if (res) {
+            qemu_rect_init(res, 0, 0, 0, 0);
+        }
+
+        return false;
+    }
+
+    if (res) {
+        qemu_rect_init(res, x1, y1, x2 - x1, y2 - y1);
+    }
+
+    return true;
+}
+
+#endif
diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
index 4265316cbb..a8e767245f 100644
--- a/hw/display/virtio-gpu.c
+++ b/hw/display/virtio-gpu.c
@@ -16,6 +16,7 @@
 #include "qemu/iov.h"
 #include "sysemu/cpus.h"
 #include "ui/console.h"
+#include "ui/rect.h"
 #include "trace.h"
 #include "sysemu/dma.h"
 #include "sysemu/sysemu.h"
@@ -503,7 +504,7 @@ static void virtio_gpu_resource_flush(VirtIOGPU *g,
     struct virtio_gpu_simple_resource *res;
     struct virtio_gpu_resource_flush rf;
     struct virtio_gpu_scanout *scanout;
-    pixman_region16_t flush_region;
+    QemuRect flush_rect;
     bool within_bounds = false;
     bool update_submitted = false;
     int i;
@@ -565,34 +566,25 @@ static void virtio_gpu_resource_flush(VirtIOGPU *g,
         return;
     }
 
-    pixman_region_init_rect(&flush_region,
-                            rf.r.x, rf.r.y, rf.r.width, rf.r.height);
+    qemu_rect_init(&flush_rect, rf.r.x, rf.r.y, rf.r.width, rf.r.height);
     for (i = 0; i < g->parent_obj.conf.max_outputs; i++) {
-        pixman_region16_t region, finalregion;
-        pixman_box16_t *extents;
+        QemuRect rect;
 
         if (!(res->scanout_bitmask & (1 << i))) {
             continue;
         }
         scanout = &g->parent_obj.scanout[i];
 
-        pixman_region_init(&finalregion);
-        pixman_region_init_rect(&region, scanout->x, scanout->y,
-                                scanout->width, scanout->height);
+        qemu_rect_init(&rect, scanout->x, scanout->y,
+                       scanout->width, scanout->height);
 
-        pixman_region_intersect(&finalregion, &flush_region, &region);
-        pixman_region_translate(&finalregion, -scanout->x, -scanout->y);
-        extents = pixman_region_extents(&finalregion);
         /* work out the area we need to update for each console */
-        dpy_gfx_update(g->parent_obj.scanout[i].con,
-                       extents->x1, extents->y1,
-                       extents->x2 - extents->x1,
-                       extents->y2 - extents->y1);
-
-        pixman_region_fini(&region);
-        pixman_region_fini(&finalregion);
+        if (qemu_rect_intersect(&flush_rect, &rect, &rect)) {
+            qemu_rect_translate(&rect, -scanout->x, -scanout->y);
+            dpy_gfx_update(g->parent_obj.scanout[i].con,
+                           rect.x, rect.y, rect.width, rect.height);
+        }
     }
-    pixman_region_fini(&flush_region);
 }
 
 static void virtio_unref_resource(pixman_image_t *image, void *data)
-- 
2.41.0