1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-25 14:47:44 +00:00

LibGfx: Small improvements to fill_rect_with_checkerboard()

- Clamp the checkerboard scanline prologue length to the total width
  of the (clipped) rect we're filling.

- Use fast_u32_fill() for the prologue and epilogue as well.
This commit is contained in:
Andreas Kling 2021-07-07 10:43:03 +02:00
parent 7cbcf5a5fa
commit f33edd33cc

View file

@ -178,8 +178,8 @@ void Painter::fill_rect_with_checkerboard(const IntRect& a_rect, const IntSize&
const size_t dst_skip = m_target->pitch() / sizeof(RGBA32);
int first_cell_column = rect.x() / cell_size.width();
int prologue_length = cell_size.width() - (rect.x() % cell_size.width());
int number_of_aligned_strips = ((rect.width() - prologue_length) / cell_size.width());
int prologue_length = min(rect.width(), cell_size.width() - (rect.x() % cell_size.width()));
int number_of_aligned_strips = (rect.width() - prologue_length) / cell_size.width();
for (int i = 0; i < rect.height(); ++i) {
int y = rect.y() + i;
@ -189,9 +189,12 @@ void Painter::fill_rect_with_checkerboard(const IntRect& a_rect, const IntSize&
// Prologue: Paint the unaligned part up to the first intersection.
int j = 0;
int cell_column = first_cell_column;
for (int p = 0; p < prologue_length; ++p) {
dst[j] = (odd_row ^ (cell_column % 2)) ? color_light.value() : color_dark.value();
++j;
{
bool odd_cell = cell_column & 1;
auto color = (odd_row ^ odd_cell) ? color_light.value() : color_dark.value();
fast_u32_fill(&dst[j], color, prologue_length);
j += prologue_length;
}
// Aligned run: Paint the maximum number of aligned cell strips.
@ -204,9 +207,13 @@ void Painter::fill_rect_with_checkerboard(const IntRect& a_rect, const IntSize&
}
// Epilogue: Paint the unaligned part until the end of the rect.
++cell_column;
for (; j < rect.width(); ++j) {
dst[j] = (odd_row ^ (cell_column % 2)) ? color_light.value() : color_dark.value();
if (j != rect.width()) {
++cell_column;
bool odd_cell = cell_column & 1;
auto color = (odd_row ^ odd_cell) ? color_light.value() : color_dark.value();
int epilogue_length = rect.width() - j;
fast_u32_fill(&dst[j], color, epilogue_length);
j += epilogue_length;
}
dst += dst_skip;