On Thu, 2002-11-21 at 11:05, Antonino Daplas wrote:
> Hi,
>
> Since I'm playing around with DirectColor visuals, I've thought of
> adding a SetColorAdjustment hook to the primary layer using the gamma
> ramp. Brightness and contrast adjustments are doable by programming the
> gamma ramp. Saturation adjustment is not as correct, since its
> implementation is best done on a per-pixel basis.
>
> The attached function is not thoroughly tested, but seems to work during
> my debugging sessions. Also, I'm not sure if the algorithm is correct.
> It requires an fbdev driver that correctly supports DirectColor visuals
> (check by running XFBDev and launching the xgamma utility).
>
>
Here's a test patch for DirectFB-0.9.15 that implements SetColorAdjustment to
fbdev.c. It has a much better saturation control which involves
adding/subtracting a proportion of medium gray.
I've tested this with a modified df_dok. Brightness works very well.
Contrast and saturation are good at high levels, but produces a dim
display at low levels.
I'm not too sure about the code since it involves adding extra
fb_cmap structures to dfb_fbdev->shared.
Tony
diff -Naur DirectFB-0.9.15-orig/src/core/fbdev/fbdev.c DirectFB-0.9.15/src/core/fbdev/fbdev.c
--- DirectFB-0.9.15-orig/src/core/fbdev/fbdev.c 2002-11-12 20:38:14.000000000 +0000
+++ DirectFB-0.9.15/src/core/fbdev/fbdev.c 2002-11-21 15:14:46.000000000 +0000
@@ -744,13 +744,19 @@
default_mode = dfb_fbdev->shared->modes;
/* set capabilities and type */
- layer_info->desc.caps = DLCAPS_SURFACE;
+ layer_info->desc.caps = DLCAPS_SURFACE | DLCAPS_CONTRAST | DLCAPS_SATURATION | DLCAPS_BRIGHTNESS;
layer_info->desc.type = DLTF_GRAPHICS;
/* set name */
snprintf( layer_info->name,
DFB_DISPLAY_LAYER_INFO_NAME_LENGTH, "Primary Layer" );
+ /* fill out default color adjustment */
+ default_adj->flags = DCAF_BRIGHTNESS | DCAF_CONTRAST | DCAF_SATURATION;
+ default_adj->brightness = 0x8000;
+ default_adj->contrast = 0x8000;
+ default_adj->saturation = 0x8000;
+
/* fill out the default configuration */
default_config->flags = DLCONF_WIDTH | DLCONF_HEIGHT |
DLCONF_PIXELFORMAT | DLCONF_BUFFERMODE;
@@ -950,15 +956,127 @@
return DFB_OK;
}
-
+
static DFBResult
primarySetColorAdjustment( DisplayLayer *layer,
void *driver_data,
void *layer_data,
DFBColorAdjustment *adj )
{
- /* maybe we could use the gamma ramp here */
- return DFB_UNSUPPORTED;
+ struct fb_cmap *cmap = &dfb_fbdev->shared->current_cmap;
+ struct fb_cmap *temp = &dfb_fbdev->shared->temp_cmap;
+ int contrast = adj->contrast >> 8;
+ int brightness = (adj->brightness >> 8) - 128;
+ int saturation = adj->saturation >> 8;
+ int r, g, b, i;
+
+ if (dfb_fbdev->shared->fix.visual != FB_VISUAL_DIRECTCOLOR)
+ return DFB_UNIMPLEMENTED;
+
+ /* Use gamma ramp to set color attributes */
+ for (i = 0; i < cmap->len; i++) {
+ r = cmap->red[i];
+ g = cmap->green[i];
+ b = cmap->blue[i];
+ r >>= 8;
+ g >>= 8;
+ b >>= 8;
+
+ /*
+ * Brightness Adjustment: Increase/Decrease each color channels
+ * by a constant amount as specified by value of brightness.
+ */
+ if (adj->flags & DCAF_BRIGHTNESS) {
+ r += brightness;
+ g += brightness;
+ b += brightness;
+
+ r = (r < 0) ? 0 : r;
+ g = (g < 0) ? 0 : g;
+ b = (b < 0) ? 0 : b;
+
+ r = (r > 255) ? 255 : r;
+ g = (g > 255) ? 255 : g;
+ b = (b > 255) ? 255 : b;
+ }
+
+ /*
+ * Contrast Adjustment: We increase/decrease the "separation"
+ * between colors in proportion to the value specified by the
+ * contrast control. Decreasing the contrast has a side effect
+ * of decreasing the brightness.
+ */
+
+ if (adj->flags & DCAF_CONTRAST) {
+ /* Increase contrast */
+ if (contrast > 128) {
+ int c = contrast - 128;
+
+ r = ((r + c/2)/c) * c;
+ g = ((g + c/2)/c) * c;
+ b = ((b + c/2)/c) * c;
+ }
+ /* Decrease contrast */
+ else if (contrast < 127) {
+ float c = (float)contrast/128.0;
+
+ r = (int)((float)r * c);
+ g = (int)((float)g * c);
+ b = (int)((float)b * c);
+ }
+ }
+
+ /*
+ * Saturation Adjustment: This is is a better implementation.
+ * Saturation is implemented by "mixing" a proportion of medium
+ * gray to the color value. On the other side, "removing"
+ * a proportion of medium gray oversaturates the color.
+ */
+ if (adj->flags & DCAF_SATURATION) {
+ if (saturation > 128) {
+ float gray = ((float)saturation - 128.0)/128.0;
+ float color = 1.0 - gray;
+
+ r = (int)(((float)r - 128.0 * gray)/color);
+ g = (int)(((float)g - 128.0 * gray)/color);
+ b = (int)(((float)b - 128.0 * gray)/color);
+ }
+ else if (saturation < 128) {
+ float color = (float)saturation/128.0;
+ float gray = 1.0 - color;
+
+ r = (int)(((float) r * color) + (128.0 * gray));
+ g = (int)(((float) g * color) + (128.0 * gray));
+ b = (int)(((float) b * color) + (128.0 * gray));
+ }
+
+ r = (r < 0) ? 0 : r;
+ g = (g < 0) ? 0 : g;
+ b = (b < 0) ? 0 : b;
+
+ r = (r > 255) ? 255 : r;
+ g = (g > 255) ? 255 : g;
+ b = (b > 255) ? 255 : b;
+ }
+ r |= r << 8;
+ g |= g << 8;
+ b |= b << 8;
+
+ temp->red[i] = (unsigned short)r;
+ temp->green[i] = (unsigned short)g;
+ temp->blue[i] = (unsigned short)b;
+ }
+
+ temp->len = cmap->len;
+ temp->start = cmap->start;
+ if (ioctl( dfb_fbdev->fd, FBIOPUTCMAP, temp ) < 0) {
+ PERRORMSG( "DirectFB/core/fbdev: "
+ "Could not set the palette!\n" );
+
+ return errno2dfb(errno);
+ }
+
+ return DFB_OK;
}
static DFBResult
@@ -968,31 +1086,24 @@
CorePalette *palette )
{
int i;
- struct fb_cmap cmap;
+ struct fb_cmap *cmap = &dfb_fbdev->shared->current_cmap;
DFB_ASSERT( layer != NULL );
DFB_ASSERT( palette != NULL );
- cmap.start = 0;
- cmap.len = palette->num_entries;
- cmap.red = (__u16*)alloca( 2 * cmap.len );
- cmap.green = (__u16*)alloca( 2 * cmap.len );
- cmap.blue = (__u16*)alloca( 2 * cmap.len );
- cmap.transp = (__u16*)alloca( 2 * cmap.len );
-
- for (i = 0; i < cmap.len; i++) {
- cmap.red[i] = palette->entries[i].r;
- cmap.green[i] = palette->entries[i].g;
- cmap.blue[i] = palette->entries[i].b;
- cmap.transp[i] = palette->entries[i].a;
-
- cmap.red[i] |= cmap.red[i] << 8;
- cmap.green[i] |= cmap.green[i] << 8;
- cmap.blue[i] |= cmap.blue[i] << 8;
- cmap.transp[i] |= cmap.transp[i] << 8;
+ for (i = 0; i < cmap->len; i++) {
+ cmap->red[i] = palette->entries[i].r;
+ cmap->green[i] = palette->entries[i].g;
+ cmap->blue[i] = palette->entries[i].b;
+ cmap->transp[i] = palette->entries[i].a;
+
+ cmap->red[i] |= cmap->red[i] << 8;
+ cmap->green[i] |= cmap->green[i] << 8;
+ cmap->blue[i] |= cmap->blue[i] << 8;
+ cmap->transp[i] |= cmap->transp[i] << 8;
}
- if (ioctl( dfb_fbdev->fd, FBIOPUTCMAP, &cmap ) < 0) {
+ if (ioctl( dfb_fbdev->fd, FBIOPUTCMAP, cmap ) < 0) {
PERRORMSG( "DirectFB/core/fbdev: "
"Could not set the palette!\n" );
@@ -1352,7 +1463,10 @@
/* To get the new pitch */
ioctl( dfb_fbdev->fd, FBIOGET_FSCREENINFO, &fix );
-
+
+ /* ++Tony: Other information (such as visual formats) will also change */
+ dfb_fbdev->shared->fix = fix;
+
dfb_gfxcard_adjust_heap_offset( var.yres_virtual * fix.line_length );
surface->front_buffer->surface = surface;
@@ -1512,7 +1626,6 @@
return ret;
}
-
static DFBResult dfb_fbdev_set_gamma_ramp( DFBSurfacePixelFormat format )
{
int i;
@@ -1520,11 +1633,14 @@
int red_size = 0;
int green_size = 0;
int blue_size = 0;
+ int red_max = 0;
+ int green_max = 0;
+ int blue_max = 0;
struct fb_cmap cmap;
if (!dfb_fbdev) {
- BUG( "dfb_fbdev_set_gamme_ramp() called while dfb_fbdev == NULL!" );
+ BUG( "dfb_fbdev_set_gamma_ramp() called while dfb_fbdev == NULL!" );
return DFB_BUG;
}
@@ -1551,23 +1667,54 @@
return DFB_OK;
}
+ /*
+ * ++Tony: gamma ramp must be set differently if in DirectColor,
+ * ie, to mimic TrueColor, index == color[index].
+ */
+ if (dfb_fbdev->shared->fix.visual == FB_VISUAL_DIRECTCOLOR) {
+ red_max = 65536 / (256/red_size);
+ green_max = 65536 / (256/green_size);
+ blue_max = 65536 / (256/blue_size);
+ }
+ else {
+ red_max = red_size;
+ green_max = green_size;
+ blue_max = blue_size;
+ }
+
cmap.start = 0;
- /* assume green to have most weight */
cmap.len = green_size;
- cmap.red = (__u16*)alloca( 2 * green_size );
- cmap.green = (__u16*)alloca( 2 * green_size );
- cmap.blue = (__u16*)alloca( 2 * green_size );
+ cmap.red = (__u16*)alloca( 2 * 256 );
+ cmap.green = (__u16*)alloca( 2 * 256 );
+ cmap.blue = (__u16*)alloca( 2 * 256 );
cmap.transp = NULL;
+ dfb_fbdev->shared->temp_cmap = cmap;
+
+ cmap.red = (__u16*)alloca( 2 * 256 );
+ cmap.green = (__u16*)alloca( 2 * 256 );
+ cmap.blue = (__u16*)alloca( 2 * 256 );
for (i = 0; i < red_size; i++)
- cmap.red[i] = dfb_fbdev_calc_gamma( i, red_size );
+ cmap.red[i] = dfb_fbdev_calc_gamma( i, red_max );
for (i = 0; i < green_size; i++)
- cmap.green[i] = dfb_fbdev_calc_gamma( i, green_size );
+ cmap.green[i] = dfb_fbdev_calc_gamma( i, green_max );
for (i = 0; i < blue_size; i++)
- cmap.blue[i] = dfb_fbdev_calc_gamma( i, blue_size );
+ cmap.blue[i] = dfb_fbdev_calc_gamma( i, blue_max );
+
+ /* ++Tony: Some drivers use the upper byte, some use the lower */
+ if (dfb_fbdev->shared->fix.visual == FB_VISUAL_DIRECTCOLOR) {
+ for (i = 0; i < red_size; i++)
+ cmap.red[i] |= cmap.red[i] << 8;
+
+ for (i = 0; i < green_size; i++)
+ cmap.green[i] |= cmap.green[i] << 8;
+
+ for (i = 0; i < blue_size; i++)
+ cmap.blue[i] |= cmap.blue[i] << 8;
+ }
if (ioctl( dfb_fbdev->fd, FBIOPUTCMAP, &cmap ) < 0) {
PERRORMSG( "DirectFB/core/fbdev: "
@@ -1576,6 +1723,7 @@
return errno2dfb(errno);
}
+ dfb_fbdev->shared->current_cmap = cmap;
return DFB_OK;
}
diff -Naur DirectFB-0.9.15-orig/src/core/fbdev/fbdev.h DirectFB-0.9.15/src/core/fbdev/fbdev.h
--- DirectFB-0.9.15-orig/src/core/fbdev/fbdev.h 2002-09-10 15:41:13.000000000 +0000
+++ DirectFB-0.9.15/src/core/fbdev/fbdev.h 2002-11-21 14:42:26.000000000 +0000
@@ -44,6 +44,10 @@
struct fb_var_screeninfo orig_var; /* fbdev variable screeninfo
before DirectFB was started */
struct fb_cmap orig_cmap; /* original palette */
+
+ struct fb_cmap current_cmap; /* our copy of the cmap */
+
+ struct fb_cmap temp_cmap; /* scratch */
} FBDevShared;
typedef struct {
