Current colors.
#define DIFFSTATE_REMOVED_DEFAULT_BG RGB(255,100,100) #define DIFFSTATE_REMOVEDWHITESPACE_DEFAULT_BG RGB(255,100,100) #define DIFFSTATE_ADDED_DEFAULT_BG RGB(255,255,0) #define DIFFSTATE_ADDEDWHITESPACE_DEFAULT_BG RGB(255,255,0) #define DIFFSTATE_WHITESPACE_DEFAULT_BG RGB(180,180,255) #define DIFFSTATE_WHITESPACE_DIFF_DEFAULT_BG RGB(255,255,0) #define DIFFSTATE_EMPTY_DEFAULT_BG RGB(200,200,200) #define DIFFSTATE_CONFLICTED_DEFAULT_BG RGB(255,0,0) #define DIFFSTATE_CONFLICTADDED_DEFAULT_BG RGB(255,100,0) #define DIFFSTATE_CONFLICTEMPTY_DEFAULT_BG RGB(255,50,50) #define DIFFSTATE_IDENTICALREMOVED_DEFAULT_BG RGB(255,200,200) #define DIFFSTATE_IDENTICALADDED_DEFAULT_BG RGB(180,255,180) #define DIFFSTATE_THEIRSREMOVED_DEFAULT_BG RGB(255,120,200) #define DIFFSTATE_THEIRSADDED_DEFAULT_BG RGB(120,255,180) #define DIFFSTATE_YOURSREMOVED_DEFAULT_BG RGB(255,200,120) #define DIFFSTATE_YOURSADDED_DEFAULT_BG RGB(180,255,120) COLORREF CLineDiffBar::m_BinDiffColors [10] = { RGB(0x00, 0xCC, 0x00), RGB(0xff, 0x80, 0x00), RGB(0x00, 0x66, 0xb3), RGB(0xff, 0xcc, 0x00), RGB(0x33, 0x00, 0x99), RGB(0xcc, 0xff, 0x00), RGB(0x00, 0x99, 0x99), RGB(0xff, 0xb2, 0x00), RGB(0xcb, 0xff, 0x00), RGB(0x41, 0x00, 0x99), };

Proposed line-diff colors.
COLORREF CLineDiffBar::m_BinDiffColors [10] = { RGB(0x00, 0x81, 0x00), RGB(0x00, 0x8f, 0x00), RGB(0x00, 0x9d, 0x00), RGB(0x00, 0xab, 0x00), RGB(0x00, 0xb9, 0x00), RGB(0x00, 0xc7, 0x00), RGB(0x00, 0xd5, 0x00), RGB(0x00, 0xe3, 0x00), RGB(0x00, 0xf1, 0x00), RGB(0x00, 0xff, 0x00), };

Proposed line-diff colors 2 (add some whiteness ==> more contrast?).
COLORREF CLineDiffBar::m_BinDiffColors [10] = { RGB(0x00, 0x81, 0x00), RGB(0x00, 0x9d, 0x00), RGB(0x00, 0xb9, 0x00), RGB(0x00, 0xd5, 0x00), RGB(0x00, 0xf1, 0x00), RGB(0x0e, 0xff, 0x0e), RGB(0x2a, 0xff, 0x2a), RGB(0x46, 0xff, 0x46), RGB(0x62, 0xff, 0x62), RGB(0x7e, 0xff, 0x7e), };