Add a RGB_Blend() variant
Add RgbBlend(), which is the same as RGB_Blend() but:
- Returns the result instead of using an out-parameter.
- Takes the input color channels as FX_XXX_STRUCT<uint8_t>.
This will be useful as more callers switch to using
FX_XXX_STRUCT<uint8_t> instead of dealing with raw bytes.
Change-Id: I4228866dd92235a45bf1030e1f311e83a78b2f70
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/123110
Reviewed-by: Tom Sepez <tsepez@google.com>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/core/fxge/dib/cfx_scanlinecompositor.cpp b/core/fxge/dib/cfx_scanlinecompositor.cpp
index 669f06d..a12aba0 100644
--- a/core/fxge/dib/cfx_scanlinecompositor.cpp
+++ b/core/fxge/dib/cfx_scanlinecompositor.cpp
@@ -72,32 +72,45 @@
return color;
}
+template <typename T, typename U>
+FX_RGB_STRUCT<int> RgbBlend(BlendMode blend_type,
+ const T& src_in,
+ const U& back_in) {
+ FX_RGB_STRUCT<int> src = {
+ .red = src_in.red, .green = src_in.green, .blue = src_in.blue};
+ FX_RGB_STRUCT<int> back = {
+ .red = back_in.red, .green = back_in.green, .blue = back_in.blue};
+ FX_RGB_STRUCT<int> result;
+ switch (blend_type) {
+ case BlendMode::kHue:
+ result = SetLum(SetSat(src, Sat(back)), Lum(back));
+ break;
+ case BlendMode::kSaturation:
+ result = SetLum(SetSat(back, Sat(src)), Lum(back));
+ break;
+ case BlendMode::kColor:
+ result = SetLum(src, Lum(back));
+ break;
+ case BlendMode::kLuminosity:
+ result = SetLum(back, Lum(src));
+ break;
+ default:
+ break;
+ }
+ return result;
+}
+
+// Prefer RgbBlend() above in new code.
void RGB_Blend(BlendMode blend_mode,
const uint8_t* src_scan,
const uint8_t* dest_scan,
int results[3]) {
UNSAFE_TODO({
- FX_RGB_STRUCT<int> result = {};
- FX_RGB_STRUCT<int> src = {
- .red = src_scan[2], .green = src_scan[1], .blue = src_scan[0]};
- FX_RGB_STRUCT<int> back = {
- .red = dest_scan[2], .green = dest_scan[1], .blue = dest_scan[0]};
- switch (blend_mode) {
- case BlendMode::kHue:
- result = SetLum(SetSat(src, Sat(back)), Lum(back));
- break;
- case BlendMode::kSaturation:
- result = SetLum(SetSat(back, Sat(src)), Lum(back));
- break;
- case BlendMode::kColor:
- result = SetLum(src, Lum(back));
- break;
- case BlendMode::kLuminosity:
- result = SetLum(back, Lum(src));
- break;
- default:
- break;
- }
+ FX_BGR_STRUCT<uint8_t> src = {
+ .blue = src_scan[0], .green = src_scan[1], .red = src_scan[2]};
+ FX_BGR_STRUCT<uint8_t> back = {
+ .blue = dest_scan[0], .green = dest_scan[1], .red = dest_scan[2]};
+ FX_RGB_STRUCT<int> result = RgbBlend(blend_mode, src, back);
results[0] = result.blue;
results[1] = result.green;
results[2] = result.red;
