Render on a temporary surface when needed
Some platforms draw directly to the screen, which means that updates
will flicker if we draw multiple layers. Prevent this by first
composing the update on a hidden surface.
diff --git a/vncviewer/Surface_OSX.cxx b/vncviewer/Surface_OSX.cxx
index c51e47f..dbf0c41 100644
--- a/vncviewer/Surface_OSX.cxx
+++ b/vncviewer/Surface_OSX.cxx
@@ -28,6 +28,32 @@
#include "Surface.h"
+static void render(CGContextRef gc, CGImageRef image,
+ int src_x, int src_y, int src_w, int src_h,
+ int x, int y, int w, int h)
+{
+ CGRect rect;
+
+ CGContextSaveGState(gc);
+
+ // We have to use clipping to partially display an image
+ rect.origin.x = x;
+ rect.origin.y = y;
+ rect.size.width = w;
+ rect.size.height = h;
+
+ CGContextClipToRect(gc, rect);
+
+ rect.origin.x = x - src_x;
+ rect.origin.y = y - src_y;
+ rect.size.width = src_w;
+ rect.size.height = src_h;
+
+ CGContextDrawImage(gc, rect, image);
+
+ CGContextRestoreGState(gc);
+}
+
void Surface::clear(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
{
unsigned char* out;
@@ -50,8 +76,6 @@
void Surface::draw(int src_x, int src_y, int x, int y, int w, int h)
{
- CGRect rect;
-
CGContextSaveGState(fl_gc);
// Reset the transformation matrix back to the default identity
@@ -62,24 +86,39 @@
src_y = height() - (src_y + h);
y = Fl_Window::current()->h() - (y + h);
- // We have to use clipping to partially display an image
- rect.origin.x = x;
- rect.origin.y = y;
- rect.size.width = w;
- rect.size.height = h;
-
- CGContextClipToRect(fl_gc, rect);
-
- rect.origin.x = x - src_x;
- rect.origin.y = y - src_y;
- rect.size.width = width();
- rect.size.height = height();
-
- CGContextDrawImage(fl_gc, rect, image);
+ render(fl_gc, image, src_x, src_y, width(), height(), x, y, w, h);
CGContextRestoreGState(fl_gc);
}
+void Surface::draw(Surface* dst, int src_x, int src_y, int x, int y, int w, int h)
+{
+ CGColorSpaceRef lut;
+ CGContextRef bitmap;
+
+ lut = CGDisplayCopyColorSpace(kCGDirectMainDisplay);
+ if (!lut) {
+ lut = CGColorSpaceCreateDeviceRGB();
+ if (!lut)
+ throw rdr::Exception("CGColorSpaceCreateDeviceRGB");
+ }
+
+ bitmap = CGBitmapContextCreate(dst->data, dst->width(),
+ dst->height(), 8, dst->width()*4, lut,
+ kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little);
+ CGColorSpaceRelease(lut);
+ if (!bitmap)
+ throw rdr::Exception("CGBitmapContextCreate");
+
+ // macOS Coordinates are from bottom left, not top left
+ src_y = height() - (src_y + h);
+ y = dst->height() - (y + h);
+
+ render(bitmap, image, src_x, src_y, width(), height(), x, y, w, h);
+
+ CGContextRelease(bitmap);
+}
+
void Surface::alloc()
{
CGColorSpaceRef lut;