From b2e1763c7d54e76a49f6f4434996f37882ae2171 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Sun, 18 Sep 2011 14:04:19 -0400 Subject: Round correctly when converting colors to integers. --- libdimension/png.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'libdimension/png.c') diff --git a/libdimension/png.c b/libdimension/png.c index 7f5da8f..21ad764 100644 --- a/libdimension/png.c +++ b/libdimension/png.c @@ -67,12 +67,12 @@ dmnsn_png_optimizer_fn(const dmnsn_canvas *canvas, color = dmnsn_get_pixel(canvas, x, y); color = dmnsn_remove_filter(color); color = dmnsn_color_to_sRGB(color); + color = dmnsn_color_saturate(color); - /* Saturate R, G, and B to [0, UINT16_MAX] */ - pixel[0] = dmnsn_min(dmnsn_max(color.R, 0.0), 1.0)*UINT16_MAX; - pixel[1] = dmnsn_min(dmnsn_max(color.G, 0.0), 1.0)*UINT16_MAX; - pixel[2] = dmnsn_min(dmnsn_max(color.B, 0.0), 1.0)*UINT16_MAX; - pixel[3] = dmnsn_min(dmnsn_max(color.trans, 0.0), 1.0)*UINT16_MAX; + pixel[0] = lround(color.R*UINT16_MAX); + pixel[1] = lround(color.G*UINT16_MAX); + pixel[2] = lround(color.B*UINT16_MAX); + pixel[3] = lround(color.trans*UINT16_MAX); } /** Payload type for PNG write thread callback. */ @@ -241,13 +241,12 @@ dmnsn_png_write_canvas_thread(void *ptr) dmnsn_color color = dmnsn_get_pixel(payload->canvas, x, height - y - 1); color = dmnsn_remove_filter(color); color = dmnsn_color_to_sRGB(color); + color = dmnsn_color_saturate(color); - /* Saturate R, G, and B to [0, UINT16_MAX] */ - - row[4*x] = dmnsn_min(dmnsn_max(color.R, 0.0), 1.0)*UINT16_MAX; - row[4*x + 1] = dmnsn_min(dmnsn_max(color.G, 0.0), 1.0)*UINT16_MAX; - row[4*x + 2] = dmnsn_min(dmnsn_max(color.B, 0.0), 1.0)*UINT16_MAX; - row[4*x + 3] = dmnsn_min(dmnsn_max(color.trans, 0.0), 1.0)*UINT16_MAX; + row[4*x] = lround(color.R*UINT16_MAX); + row[4*x + 1] = lround(color.G*UINT16_MAX); + row[4*x + 2] = lround(color.B*UINT16_MAX); + row[4*x + 3] = lround(color.trans*UINT16_MAX); } /* Write the row */ -- cgit v1.2.3