(svn r26252) -Codechange: deduplicate code for margin case (MJP)

4 files changed, 414 insertions, 536 deletions

diff --git a/src/blitter/32bpp_anim_sse4.cpp b/src/blitter/32bpp_anim_sse4.cpp
index 3229338cd..e1072dd5f 100644
--- a/src/blitter/32bpp_anim_sse4.cpp
+++ b/src/blitter/32bpp_anim_sse4.cpp
@@ -30,12 +30,12 @@ IGNORE_UNINITIALIZED_WARNING_START
 template <BlitterMode mode, Blitter_32bppSSE2::ReadMode read_mode, Blitter_32bppSSE2::BlockType bt_last>
 inline void Blitter_32bppSSE4_Anim::Draw(const Blitter::BlitterParams *bp, ZoomLevel zoom)
 {
+	const byte * const remap = bp->remap;
 	Colour *dst_line = (Colour *) bp->dst + bp->top * bp->pitch + bp->left;
 	uint16 *anim_line = this->anim_buf + ((uint32 *)bp->dst - (uint32 *)_screen.dst_ptr) + bp->top * this->anim_buf_width + bp->left;
 	int effective_width = bp->width;
 
 	/* Find where to start reading in the source sprite. */
-	const byte * const remap = bp->remap;
 	const Blitter_32bppSSE_Base::SpriteData * const sd = (const Blitter_32bppSSE_Base::SpriteData *) bp->sprite;
 	const SpriteInfo * const si = &sd->infos[zoom];
 	const MapValue *src_mv_line = (const MapValue *) &sd->data[si->mv_offset] + bp->skip_top * si->sprite_width;
@@ -45,6 +45,7 @@ inline void Blitter_32bppSSE4_Anim::Draw(const Blitter::BlitterParams *bp, ZoomL
 		src_rgba_line += bp->skip_left;
 		src_mv_line += bp->skip_left;
 	}
+	const MapValue *src_mv = src_mv_line;
 
 	/* Load these variables into register before loop. */
 	const __m128i a_cm        = ALPHA_CONTROL_MASK;
@@ -59,233 +60,202 @@ inline void Blitter_32bppSSE4_Anim::Draw(const Blitter::BlitterParams *bp, ZoomL
 	for (int y = bp->height; y != 0; y--) {
 		Colour *dst = dst_line;
 		const Colour *src = src_rgba_line + META_LENGTH;
-		const MapValue *src_mv = src_mv_line;
+		if (mode != BM_TRANSPARENT) src_mv = src_mv_line;
 		uint16 *anim = anim_line;
 
-		switch (mode) {
-			default: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						src_mv += src_rgba_line[0].data;
-						anim += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - (delta_diff & ~1);
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
-					}
+		if (read_mode == RM_WITH_MARGIN) {
+			anim += src_rgba_line[0].data;
+			src += src_rgba_line[0].data;
+			dst += src_rgba_line[0].data;
+			if (mode != BM_TRANSPARENT) src_mv += src_rgba_line[0].data;
+			const int width_diff = si->sprite_width - bp->width;
+			effective_width = bp->width - (int) src_rgba_line[0].data;
+			const int delta_diff = (int) src_rgba_line[1].data - width_diff;
+			const int new_width = effective_width - delta_diff;
+			effective_width = delta_diff > 0 ? new_width : effective_width;
+			if (effective_width <= 0) goto next_line;
+		}
 
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width/2; x != 0; x--) {
-							uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
+		switch (mode) {
+			default:
+				for (uint x = (uint) effective_width/2; x != 0; x--) {
+					uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
 
-							/* Remap colours. */
-							const byte m0 = mvX2;
-							if (m0 >= PALETTE_ANIM_START) {
-								const Colour c0 = (this->LookupColourInPalette(m0).data & 0x00FFFFFF) | (src[0].data & 0xFF000000);
-								INSR32(AdjustBrightness(c0, (byte) (mvX2 >> 8)).data, srcABCD, 0);
-							}
-							const byte m1 = mvX2 >> 16;
-							if (m1 >= PALETTE_ANIM_START) {
-								const Colour c1 = (this->LookupColourInPalette(m1).data & 0x00FFFFFF) | (src[1].data & 0xFF000000);
-								INSR32(AdjustBrightness(c1, (byte) (mvX2 >> 24)).data, srcABCD, 1);
-							}
+					/* Remap colours. */
+					const byte m0 = mvX2;
+					if (m0 >= PALETTE_ANIM_START) {
+						const Colour c0 = (this->LookupColourInPalette(m0).data & 0x00FFFFFF) | (src[0].data & 0xFF000000);
+						INSR32(AdjustBrightness(c0, (byte) (mvX2 >> 8)).data, srcABCD, 0);
+					}
+					const byte m1 = mvX2 >> 16;
+					if (m1 >= PALETTE_ANIM_START) {
+						const Colour c1 = (this->LookupColourInPalette(m1).data & 0x00FFFFFF) | (src[1].data & 0xFF000000);
+						INSR32(AdjustBrightness(c1, (byte) (mvX2 >> 24)).data, srcABCD, 1);
+					}
 
-							/* Update anim buffer. */
-							const byte a0 = src[0].a;
-							const byte a1 = src[1].a;
-							uint32 anim01 = 0;
-							if (a0 == 255) {
-								if (a1 == 255) {
-									*(uint32*) anim = mvX2;
-									goto bmno_full_opacity;
-								}
-								anim01 = (uint16) mvX2;
-							} else if (a0 == 0) {
-								if (a1 == 0) {
-									goto bmno_full_transparency;
-								} else {
-									if (a1 == 255) anim[1] = (uint16) (mvX2 >> 16);
-									goto bmno_alpha_blend;
-								}
-							}
-							if (a1 > 0) {
-								if (a1 == 255) anim01 |= mvX2 & 0xFFFF0000;
-								*(uint32*) anim = anim01;
-							} else {
-								anim[0] = (uint16) anim01;
-							}
+					/* Update anim buffer. */
+					const byte a0 = src[0].a;
+					const byte a1 = src[1].a;
+					uint32 anim01 = 0;
+					if (a0 == 255) {
+						if (a1 == 255) {
+							*(uint32*) anim = mvX2;
+							goto bmno_full_opacity;
+						}
+						anim01 = (uint16) mvX2;
+					} else if (a0 == 0) {
+						if (a1 == 0) {
+							goto bmno_full_transparency;
+						} else {
+							if (a1 == 255) anim[1] = (uint16) (mvX2 >> 16);
+							goto bmno_alpha_blend;
+						}
+					}
+					if (a1 > 0) {
+						if (a1 == 255) anim01 |= mvX2 & 0xFFFF0000;
+						*(uint32*) anim = anim01;
+					} else {
+						anim[0] = (uint16) anim01;
+					}
 
-							/* Blend colours. */
+					/* Blend colours. */
 bmno_alpha_blend:
-							ALPHA_BLEND_2();
+					ALPHA_BLEND_2();
 bmno_full_opacity:
-							_mm_storel_epi64((__m128i *) dst, srcABCD);
+					_mm_storel_epi64((__m128i *) dst, srcABCD);
 bmno_full_transparency:
-							src_mv += 2;
-							src += 2;
-							anim += 2;
-							dst += 2;
-						}
+					src_mv += 2;
+					src += 2;
+					anim += 2;
+					dst += 2;
+				}
 
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							if (src->a == 0) {
-							} else if (src->a == 255) {
-								*anim = *(const uint16*) src_mv;
-								*dst = (src_mv->m >= PALETTE_ANIM_START) ? AdjustBrightness(LookupColourInPalette(src_mv->m), src_mv->v) : *src;
-							} else {
-								*anim = 0;
-								__m128i srcABCD;
-								__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-								if (src_mv->m >= PALETTE_ANIM_START) {
-									Colour colour = AdjustBrightness(LookupColourInPalette(src_mv->m), src_mv->v);
-									colour.a = src->a;
-									srcABCD = _mm_cvtsi32_si128(colour.data);
-								} else {
-									srcABCD = _mm_cvtsi32_si128(src->data);
-								}
-								ALPHA_BLEND_2();
-								dst->data = _mm_cvtsi128_si32(srcABCD);
-							}
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					if (src->a == 0) {
+					} else if (src->a == 255) {
+						*anim = *(const uint16*) src_mv;
+						*dst = (src_mv->m >= PALETTE_ANIM_START) ? AdjustBrightness(LookupColourInPalette(src_mv->m), src_mv->v) : *src;
+					} else {
+						*anim = 0;
+						__m128i srcABCD;
+						__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+						if (src_mv->m >= PALETTE_ANIM_START) {
+							Colour colour = AdjustBrightness(LookupColourInPalette(src_mv->m), src_mv->v);
+							colour.a = src->a;
+							srcABCD = _mm_cvtsi32_si128(colour.data);
+						} else {
+							srcABCD = _mm_cvtsi32_si128(src->data);
 						}
-						break;
+						ALPHA_BLEND_2();
+						dst->data = _mm_cvtsi128_si32(srcABCD);
 					}
-
-					default: NOT_REACHED();
 				}
 				break;
-			}
-
-			case BM_COLOUR_REMAP: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						src_mv += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						anim += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - delta_diff;
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
-					}
 
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width / 2; x != 0; x--) {
-							uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-
-							/* Remap colours. */
-							const uint m0 = (byte) mvX2;
-							const uint r0 = remap[m0];
-							const uint m1 = (byte) (mvX2 >> 16);
-							const uint r1 = remap[m1];
-							if (mvX2 & 0x00FF00FF) {
-								/* Written so the compiler uses CMOV. */
-								const Colour src0 = src[0];
-								const Colour c0map = (this->LookupColourInPalette(r0).data & 0x00FFFFFF) | (src0.data & 0xFF000000);
-								Colour c0 = dst[0];
-								c0 = r0 == 0 ? c0 : c0map;
-								c0 = m0 != 0 ? c0 : src0;
-								INSR32(c0.data, srcABCD, 0);
-
-								const Colour src1 = src[1];
-								const Colour c1map = (this->LookupColourInPalette(r1).data & 0x00FFFFFF) | (src1.data & 0xFF000000);
-								Colour c1 = dst[1];
-								c1 = r1 == 0 ? c1 : c1map;
-								c1 = m1 != 0 ? c1 : src1;
-								INSR32(c1.data, srcABCD, 1);
+			case BM_COLOUR_REMAP:
+				for (uint x = (uint) effective_width / 2; x != 0; x--) {
+					uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
 
-								if ((mvX2 & 0xFF00FF00) != 0x80008000) {
-									ADJUST_BRIGHTNESS_2(srcABCD, mvX2);
-								}
-							}
+					/* Remap colours. */
+					const uint m0 = (byte) mvX2;
+					const uint r0 = remap[m0];
+					const uint m1 = (byte) (mvX2 >> 16);
+					const uint r1 = remap[m1];
+					if (mvX2 & 0x00FF00FF) {
+						/* Written so the compiler uses CMOV. */
+						const Colour src0 = src[0];
+						const Colour c0map = (this->LookupColourInPalette(r0).data & 0x00FFFFFF) | (src0.data & 0xFF000000);
+						Colour c0 = dst[0];
+						c0 = r0 == 0 ? c0 : c0map;
+						c0 = m0 != 0 ? c0 : src0;
+						INSR32(c0.data, srcABCD, 0);
+
+						const Colour src1 = src[1];
+						const Colour c1map = (this->LookupColourInPalette(r1).data & 0x00FFFFFF) | (src1.data & 0xFF000000);
+						Colour c1 = dst[1];
+						c1 = r1 == 0 ? c1 : c1map;
+						c1 = m1 != 0 ? c1 : src1;
+						INSR32(c1.data, srcABCD, 1);
+
+						if ((mvX2 & 0xFF00FF00) != 0x80008000) {
+							ADJUST_BRIGHTNESS_2(srcABCD, mvX2);
+						}
+					}
 
-							/* Update anim buffer. */
-							const byte a0 = src[0].a;
-							const byte a1 = src[1].a;
-							uint32 anim01 = mvX2 & 0xFF00FF00;
-							if (a0 == 255) {
-								anim01 |= r0;
-								if (a1 == 255) {
-									*(uint32*) anim = anim01 | (r1 << 16);
-									goto bmcr_full_opacity;
-								}
-							} else if (a0 == 0) {
-								if (a1 == 0) {
-									goto bmcr_full_transparency;
-								} else {
-									if (a1 == 255) {
-										anim[1] = r1 | (anim01 >> 16);
-									}
-									goto bmcr_alpha_blend;
-								}
-							}
-							if (a1 > 0) {
-								if (a1 == 255) anim01 |= r1 << 16;
-								*(uint32*) anim = anim01;
-							} else {
-								anim[0] = (uint16) anim01;
+					/* Update anim buffer. */
+					const byte a0 = src[0].a;
+					const byte a1 = src[1].a;
+					uint32 anim01 = mvX2 & 0xFF00FF00;
+					if (a0 == 255) {
+						anim01 |= r0;
+						if (a1 == 255) {
+							*(uint32*) anim = anim01 | (r1 << 16);
+							goto bmcr_full_opacity;
+						}
+					} else if (a0 == 0) {
+						if (a1 == 0) {
+							goto bmcr_full_transparency;
+						} else {
+							if (a1 == 255) {
+								anim[1] = r1 | (anim01 >> 16);
 							}
+							goto bmcr_alpha_blend;
+						}
+					}
+					if (a1 > 0) {
+						if (a1 == 255) anim01 |= r1 << 16;
+						*(uint32*) anim = anim01;
+					} else {
+						anim[0] = (uint16) anim01;
+					}
 
-							/* Blend colours. */
+					/* Blend colours. */
 bmcr_alpha_blend:
-							ALPHA_BLEND_2();
+					ALPHA_BLEND_2();
 bmcr_full_opacity:
-							_mm_storel_epi64((__m128i *) dst, srcABCD);
+					_mm_storel_epi64((__m128i *) dst, srcABCD);
 bmcr_full_transparency:
-							src_mv += 2;
-							dst += 2;
-							src += 2;
-							anim += 2;
-						}
+					src_mv += 2;
+					dst += 2;
+					src += 2;
+					anim += 2;
+				}
 
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							/* In case the m-channel is zero, do not remap this pixel in any way. */
-							__m128i srcABCD;
-							if (src->a == 0) break;
-							if (src_mv->m) {
-								const uint r = remap[src_mv->m];
-								*anim = (src->a == 255) ? r | ((uint16) src_mv->v << 8 ) : 0;
-								if (r != 0) {
-									Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
-									if (src->a == 255) {
-										*dst = remapped_colour;
-									} else {
-										remapped_colour.a = src->a;
-										srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
-										goto bmcr_alpha_blend_single;
-									}
-								}
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					/* In case the m-channel is zero, do not remap this pixel in any way. */
+					__m128i srcABCD;
+					if (src->a == 0) break;
+					if (src_mv->m) {
+						const uint r = remap[src_mv->m];
+						*anim = (src->a == 255) ? r | ((uint16) src_mv->v << 8 ) : 0;
+						if (r != 0) {
+							Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
+							if (src->a == 255) {
+								*dst = remapped_colour;
 							} else {
-								*anim = 0;
-								srcABCD = _mm_cvtsi32_si128(src->data);
-								if (src->a < 255) {
-bmcr_alpha_blend_single:
-									__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-									ALPHA_BLEND_2();
-								}
-								dst->data = _mm_cvtsi128_si32(srcABCD);
+								remapped_colour.a = src->a;
+								srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
+								goto bmcr_alpha_blend_single;
 							}
 						}
-						break;
+					} else {
+						*anim = 0;
+						srcABCD = _mm_cvtsi32_si128(src->data);
+						if (src->a < 255) {
+bmcr_alpha_blend_single:
+							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+							ALPHA_BLEND_2();
+						}
+						dst->data = _mm_cvtsi128_si32(srcABCD);
 					}
-
-					default: NOT_REACHED();
 				}
 				break;
-			}
 
-			case BM_TRANSPARENT: {
+			case BM_TRANSPARENT:
 				/* Make the current colour a bit more black, so it looks like this image is transparent. */
 				for (uint x = (uint) bp->width / 2; x > 0; x--) {
 					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
@@ -298,6 +268,7 @@ bmcr_alpha_blend_single:
 					if (src[-2].a) anim[-2] = 0;
 					if (src[-1].a) anim[-1] = 0;
 				}
+
 				if ((bt_last == BT_NONE && bp->width & 1) || bt_last == BT_ODD) {
 					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
 					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
@@ -306,10 +277,10 @@ bmcr_alpha_blend_single:
 					if (src[0].a) anim[0] = 0;
 				}
 				break;
-			}
 		}
 
-		src_mv_line += si->sprite_width;
+next_line:
+		if (mode != BM_TRANSPARENT) src_mv_line += si->sprite_width;
 		src_rgba_line = (const Colour*) ((const byte*) src_rgba_line + si->sprite_line_size);
 		dst_line += bp->pitch;
 		anim_line += this->anim_buf_width;
@@ -328,19 +299,15 @@ void Blitter_32bppSSE4_Anim::Draw(Blitter::BlitterParams *bp, BlitterMode mode,
 {
 	switch (mode) {
 		case BM_NORMAL: {
-			const BlockType bt_last = (BlockType) (bp->width & 1);
 			if (bp->skip_left != 0 || bp->width <= MARGIN_NORMAL_THRESHOLD) {
+				const BlockType bt_last = (BlockType) (bp->width & 1);
 				switch (bt_last) {
 					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_SKIP, BT_EVEN>(bp, zoom); return;
 					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_SKIP, BT_ODD>(bp, zoom); return;
 					default: NOT_REACHED();
 				}
 			} else {
-				switch (bt_last) {
-					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_MARGIN, BT_EVEN>(bp, zoom); return;
-					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_MARGIN, BT_ODD>(bp, zoom); return;
-					default: NOT_REACHED();
-				}
+				Draw<BM_NORMAL, RM_WITH_MARGIN, BT_NONE>(bp, zoom); return;
 			}
 			break;
 		}
diff --git a/src/blitter/32bpp_sse2.cpp b/src/blitter/32bpp_sse2.cpp
index a5d8a1987..ddaa352e2 100644
--- a/src/blitter/32bpp_sse2.cpp
+++ b/src/blitter/32bpp_sse2.cpp
@@ -30,6 +30,7 @@ IGNORE_UNINITIALIZED_WARNING_START
 template <BlitterMode mode, Blitter_32bppSSE2::ReadMode read_mode, Blitter_32bppSSE2::BlockType bt_last>
 inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel zoom)
 {
+	const byte *remap = bp->remap;
 	Colour *dst_line = (Colour *) bp->dst + bp->top * bp->pitch + bp->left;
 	int effective_width = bp->width;
 
@@ -43,6 +44,7 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
 		src_rgba_line += bp->skip_left;
 		src_mv_line += bp->skip_left;
 	}
+	const MapValue *src_mv = src_mv_line;
 
 	/* Load these variables into register before loop. */
 	const __m128i clear_hi    = CLEAR_HIGH_BYTE_MASK;
@@ -51,99 +53,71 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
 	for (int y = bp->height; y != 0; y--) {
 		Colour *dst = dst_line;
 		const Colour *src = src_rgba_line + META_LENGTH;
-		const MapValue *src_mv = src_mv_line;
+		if (mode == BM_COLOUR_REMAP) src_mv = src_mv_line;
+
+		if (read_mode == RM_WITH_MARGIN) {
+			src += src_rgba_line[0].data;
+			dst += src_rgba_line[0].data;
+			if (mode == BM_COLOUR_REMAP) src_mv += src_rgba_line[0].data;
+			const int width_diff = si->sprite_width - bp->width;
+			effective_width = bp->width - (int) src_rgba_line[0].data;
+			const int delta_diff = (int) src_rgba_line[1].data - width_diff;
+			const int new_width = effective_width - delta_diff;
+			effective_width = delta_diff > 0 ? new_width : effective_width;
+			if (effective_width <= 0) goto next_line;
+		}
 
 		switch (mode) {
-			default: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - (delta_diff & ~1);
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
-					}
-
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width / 2; x > 0; x--) {
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-							ALPHA_BLEND_2();
-							_mm_storel_epi64((__m128i*) dst, srcABCD);
-							src += 2;
-							dst += 2;
-						}
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							__m128i srcABCD = _mm_cvtsi32_si128(src->data);
-							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-							ALPHA_BLEND_2();
-							dst->data = _mm_cvtsi128_si32(srcABCD);
-						}
-						break;
-					}
+			default:
+				for (uint x = (uint) effective_width / 2; x > 0; x--) {
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
+					ALPHA_BLEND_2();
+					_mm_storel_epi64((__m128i*) dst, srcABCD);
+					src += 2;
+					dst += 2;
+				}
 
-					default: NOT_REACHED();
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
+					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+					ALPHA_BLEND_2();
+					dst->data = _mm_cvtsi128_si32(srcABCD);
 				}
 				break;
-			}
-			case BM_COLOUR_REMAP: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						src_mv += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - delta_diff;
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
-					}
 
-					case RM_WITH_SKIP: {
-						const byte *remap = bp->remap;
-						for (uint x = (uint) effective_width; x != 0; x--) {
-							/* In case the m-channel is zero, do not remap this pixel in any way. */
-							__m128i srcABCD;
-							if (src_mv->m) {
-								const uint r = remap[src_mv->m];
-								if (r != 0) {
-									Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
-									if (src->a == 255) {
-										*dst = remapped_colour;
-									} else {
-										remapped_colour.a = src->a;
-										srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
-										goto bmcr_alpha_blend_single;
-									}
-								}
+			case BM_COLOUR_REMAP:
+				for (uint x = (uint) effective_width; x != 0; x--) {
+					/* In case the m-channel is zero, do not remap this pixel in any way. */
+					__m128i srcABCD;
+					if (src_mv->m) {
+						const uint r = remap[src_mv->m];
+						if (r != 0) {
+							Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
+							if (src->a == 255) {
+								*dst = remapped_colour;
 							} else {
-								srcABCD = _mm_cvtsi32_si128(src->data);
-								if (src->a < 255) {
-bmcr_alpha_blend_single:
-									__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-									ALPHA_BLEND_2();
-								}
-								dst->data = _mm_cvtsi128_si32(srcABCD);
+								remapped_colour.a = src->a;
+								srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
+								goto bmcr_alpha_blend_single;
 							}
-							src_mv++;
-							dst++;
-							src++;
 						}
-						break;
+					} else {
+						srcABCD = _mm_cvtsi32_si128(src->data);
+						if (src->a < 255) {
+bmcr_alpha_blend_single:
+							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+							ALPHA_BLEND_2();
+						}
+						dst->data = _mm_cvtsi128_si32(srcABCD);
 					}
-
-					default: NOT_REACHED();
+					src_mv++;
+					dst++;
+					src++;
 				}
-				src_mv_line += si->sprite_width;
 				break;
-			}
-			case BM_TRANSPARENT: {
+
+			case BM_TRANSPARENT:
 				/* Make the current colour a bit more black, so it looks like this image is transparent. */
 				for (uint x = (uint) bp->width / 2; x > 0; x--) {
 					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
@@ -153,6 +127,7 @@ bmcr_alpha_blend_single:
 					src += 2;
 					dst += 2;
 				}
+
 				if ((bt_last == BT_NONE && bp->width & 1) || bt_last == BT_ODD) {
 					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
 					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
@@ -160,9 +135,10 @@ bmcr_alpha_blend_single:
 					dst->data = _mm_cvtsi128_si32(dstAB);
 				}
 				break;
-			}
 		}
 
+next_line:
+		if (mode == BM_COLOUR_REMAP) src_mv_line += si->sprite_width;
 		src_rgba_line = (const Colour*) ((const byte*) src_rgba_line + si->sprite_line_size);
 		dst_line += bp->pitch;
 	}
@@ -180,19 +156,15 @@ void Blitter_32bppSSE2::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomL
 {
 	switch (mode) {
 		case BM_NORMAL: {
-			const BlockType bt_last = (BlockType) (bp->width & 1);
 			if (bp->skip_left != 0 || bp->width <= MARGIN_NORMAL_THRESHOLD) {
+				const BlockType bt_last = (BlockType) (bp->width & 1);
 				switch (bt_last) {
 					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_SKIP, BT_EVEN>(bp, zoom); return;
 					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_SKIP, BT_ODD>(bp, zoom); return;
 					default: NOT_REACHED();
 				}
 			} else {
-				switch (bt_last) {
-					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_MARGIN, BT_EVEN>(bp, zoom); return;
-					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_MARGIN, BT_ODD>(bp, zoom); return;
-					default: NOT_REACHED();
-				}
+				Draw<BM_NORMAL, RM_WITH_MARGIN, BT_NONE>(bp, zoom); return;
 			}
 			break;
 		}
diff --git a/src/blitter/32bpp_sse4.cpp b/src/blitter/32bpp_sse4.cpp
index d43cd8cd9..6bdb9e950 100644
--- a/src/blitter/32bpp_sse4.cpp
+++ b/src/blitter/32bpp_sse4.cpp
@@ -44,6 +44,7 @@ inline void Blitter_32bppSSE4::Draw(const Blitter::BlitterParams *bp, ZoomLevel
 		src_rgba_line += bp->skip_left;
 		src_mv_line += bp->skip_left;
 	}
+	const MapValue *src_mv = src_mv_line;
 
 	/* Load these variables into register before loop. */
 	const __m128i a_cm        = ALPHA_CONTROL_MASK;
@@ -58,136 +59,107 @@ inline void Blitter_32bppSSE4::Draw(const Blitter::BlitterParams *bp, ZoomLevel
 	for (int y = bp->height; y != 0; y--) {
 		const Colour *src = src_rgba_line + META_LENGTH;
 		Colour *dst = dst_line;
-		const MapValue *src_mv = src_mv_line;
+		if (mode == BM_COLOUR_REMAP) src_mv = src_mv_line;
+
+		if (read_mode == RM_WITH_MARGIN) {
+			src += src_rgba_line[0].data;
+			dst += src_rgba_line[0].data;
+			if (mode == BM_COLOUR_REMAP) src_mv += src_rgba_line[0].data;
+			const int width_diff = si->sprite_width - bp->width;
+			effective_width = bp->width - (int) src_rgba_line[0].data;
+			const int delta_diff = (int) src_rgba_line[1].data - width_diff;
+			const int new_width = effective_width - delta_diff;
+			effective_width = delta_diff > 0 ? new_width : effective_width;
+			if (effective_width <= 0) goto next_line;
+		}
 
 		switch (mode) {
-			default: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - (delta_diff & ~1);
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
-					}
-
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width / 2; x > 0; x--) {
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-							ALPHA_BLEND_2();
-							_mm_storel_epi64((__m128i*) dst, srcABCD);
-							src += 2;
-							dst += 2;
-						}
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							__m128i srcABCD = _mm_cvtsi32_si128(src->data);
-							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-							ALPHA_BLEND_2();
-							dst->data = _mm_cvtsi128_si32(srcABCD);
-						}
-						break;
-					}
+			default:
+				for (uint x = (uint) effective_width / 2; x > 0; x--) {
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
+					ALPHA_BLEND_2();
+					_mm_storel_epi64((__m128i*) dst, srcABCD);
+					src += 2;
+					dst += 2;
+				}
 
-					default: NOT_REACHED();
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
+					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+					ALPHA_BLEND_2();
+					dst->data = _mm_cvtsi128_si32(srcABCD);
 				}
 				break;
-			}
 
-			case BM_COLOUR_REMAP: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						src_mv += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - delta_diff;
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
+			case BM_COLOUR_REMAP:
+				for (uint x = (uint) effective_width / 2; x > 0; x--) {
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
+					uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
+
+					/* Remap colours. */
+					if (mvX2 & 0x00FF00FF) {
+						/* Written so the compiler uses CMOV. */
+						const Colour src0 = src[0];
+						const uint m0 = (byte) mvX2;
+						const uint r0 = remap[m0];
+						const Colour c0map = (this->LookupColourInPalette(r0).data & 0x00FFFFFF) | (src0.data & 0xFF000000);
+						Colour c0 = 0; // Use alpha of 0 to keep dst as is.
+						c0 = r0 == 0 ? c0 : c0map;
+						c0 = m0 != 0 ? c0 : src0;
+						INSR32(c0.data, srcABCD, 0);
+
+						const Colour src1 = src[1];
+						const uint m1 = (byte) (mvX2 >> 16);
+						const uint r1 = remap[m1];
+						const Colour c1map = (this->LookupColourInPalette(r1).data & 0x00FFFFFF) | (src1.data & 0xFF000000);
+						Colour c1 = 0;
+						c1 = r1 == 0 ? c1 : c1map;
+						c1 = m1 != 0 ? c1 : src1;
+						INSR32(c1.data, srcABCD, 1);
+
+						if ((mvX2 & 0xFF00FF00) != 0x80008000) {
+							ADJUST_BRIGHTNESS_2(srcABCD, mvX2);
+						}
 					}
 
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width / 2; x > 0; x--) {
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-							uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
-
-							/* Remap colours. */
-							if (mvX2 & 0x00FF00FF) {
-								/* Written so the compiler uses CMOV. */
-								const Colour src0 = src[0];
-								const uint m0 = (byte) mvX2;
-								const uint r0 = remap[m0];
-								const Colour c0map = (this->LookupColourInPalette(r0).data & 0x00FFFFFF) | (src0.data & 0xFF000000);
-								Colour c0 = 0; // Use alpha of 0 to keep dst as is.
-								c0 = r0 == 0 ? c0 : c0map;
-								c0 = m0 != 0 ? c0 : src0;
-								INSR32(c0.data, srcABCD, 0);
-
-								const Colour src1 = src[1];
-								const uint m1 = (byte) (mvX2 >> 16);
-								const uint r1 = remap[m1];
-								const Colour c1map = (this->LookupColourInPalette(r1).data & 0x00FFFFFF) | (src1.data & 0xFF000000);
-								Colour c1 = 0;
-								c1 = r1 == 0 ? c1 : c1map;
-								c1 = m1 != 0 ? c1 : src1;
-								INSR32(c1.data, srcABCD, 1);
+					/* Blend colours. */
+					ALPHA_BLEND_2();
+					_mm_storel_epi64((__m128i *) dst, srcABCD);
+					dst += 2;
+					src += 2;
+					src_mv += 2;
+				}
 
-								if ((mvX2 & 0xFF00FF00) != 0x80008000) {
-									ADJUST_BRIGHTNESS_2(srcABCD, mvX2);
-								}
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					/* In case the m-channel is zero, do not remap this pixel in any way. */
+					__m128i srcABCD;
+					if (src_mv->m) {
+						const uint r = remap[src_mv->m];
+						if (r != 0) {
+							Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
+							if (src->a == 255) {
+								*dst = remapped_colour;
+							} else {
+								remapped_colour.a = src->a;
+								srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
+								goto bmcr_alpha_blend_single;
 							}
-
-							/* Blend colours. */
-							ALPHA_BLEND_2();
-							_mm_storel_epi64((__m128i *) dst, srcABCD);
-							dst += 2;
-							src += 2;
-							src_mv += 2;
 						}
-
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							/* In case the m-channel is zero, do not remap this pixel in any way. */
-							__m128i srcABCD;
-							if (src_mv->m) {
-								const uint r = remap[src_mv->m];
-								if (r != 0) {
-									Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
-									if (src->a == 255) {
-										*dst = remapped_colour;
-									} else {
-										remapped_colour.a = src->a;
-										srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
-										goto bmcr_alpha_blend_single;
-									}
-								}
-							} else {
-								srcABCD = _mm_cvtsi32_si128(src->data);
-								if (src->a < 255) {
+					} else {
+						srcABCD = _mm_cvtsi32_si128(src->data);
+						if (src->a < 255) {
 bmcr_alpha_blend_single:
-									__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-									ALPHA_BLEND_2();
-								}
-								dst->data = _mm_cvtsi128_si32(srcABCD);
-							}
+							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+							ALPHA_BLEND_2();
 						}
-						break;
+						dst->data = _mm_cvtsi128_si32(srcABCD);
 					}
-
-					default: NOT_REACHED();
 				}
-				src_mv_line += si->sprite_width;
 				break;
-			}
 
-			case BM_TRANSPARENT: {
+			case BM_TRANSPARENT:
 				/* Make the current colour a bit more black, so it looks like this image is transparent. */
 				for (uint x = (uint) bp->width / 2; x > 0; x--) {
 					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
@@ -197,17 +169,18 @@ bmcr_alpha_blend_single:
 					src += 2;
 					dst += 2;
 				}
+
 				if ((bt_last == BT_NONE && bp->width & 1) || bt_last == BT_ODD) {
 					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
 					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
 					DARKEN_2();
 					dst->data = _mm_cvtsi128_si32(dstAB);
 				}
-
 				break;
-			}
 		}
 
+next_line:
+		if (mode == BM_COLOUR_REMAP) src_mv_line += si->sprite_width;
 		src_rgba_line = (const Colour*) ((const byte*) src_rgba_line + si->sprite_line_size);
 		dst_line += bp->pitch;
 	}
@@ -223,21 +196,17 @@ IGNORE_UNINITIALIZED_WARNING_STOP
  */
 void Blitter_32bppSSE4::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom)
 {
-	const BlockType bt_last = (BlockType) (bp->width & 1);
 	switch (mode) {
 		case BM_NORMAL: {
 			if (bp->skip_left != 0 || bp->width <= MARGIN_NORMAL_THRESHOLD) {
+				const BlockType bt_last = (BlockType) (bp->width & 1);
 				switch (bt_last) {
 					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_SKIP, BT_EVEN>(bp, zoom); return;
 					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_SKIP, BT_ODD>(bp, zoom); return;
 					default: NOT_REACHED();
 				}
 			} else {
-				switch (bt_last) {
-					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_MARGIN, BT_EVEN>(bp, zoom); return;
-					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_MARGIN, BT_ODD>(bp, zoom); return;
-					default: NOT_REACHED();
-				}
+				Draw<BM_NORMAL, RM_WITH_MARGIN, BT_NONE>(bp, zoom); return;
 			}
 			break;
 		}
diff --git a/src/blitter/32bpp_ssse3.cpp b/src/blitter/32bpp_ssse3.cpp
index 32a981b1b..32f073d45 100644
--- a/src/blitter/32bpp_ssse3.cpp
+++ b/src/blitter/32bpp_ssse3.cpp
@@ -44,6 +44,7 @@ inline void Blitter_32bppSSSE3::Draw(const Blitter::BlitterParams *bp, ZoomLevel
 		src_rgba_line += bp->skip_left;
 		src_mv_line += bp->skip_left;
 	}
+	const MapValue *src_mv = src_mv_line;
 
 	/* Load these variables into register before loop. */
 	const __m128i a_cm        = ALPHA_CONTROL_MASK;
@@ -58,136 +59,107 @@ inline void Blitter_32bppSSSE3::Draw(const Blitter::BlitterParams *bp, ZoomLevel
 	for (int y = bp->height; y != 0; y--) {
 		Colour *dst = dst_line;
 		const Colour *src = src_rgba_line + META_LENGTH;
-		const MapValue *src_mv = src_mv_line;
+		if (mode == BM_COLOUR_REMAP) src_mv = src_mv_line;
+
+		if (read_mode == RM_WITH_MARGIN) {
+			src += src_rgba_line[0].data;
+			dst += src_rgba_line[0].data;
+			if (mode == BM_COLOUR_REMAP) src_mv += src_rgba_line[0].data;
+			const int width_diff = si->sprite_width - bp->width;
+			effective_width = bp->width - (int) src_rgba_line[0].data;
+			const int delta_diff = (int) src_rgba_line[1].data - width_diff;
+			const int new_width = effective_width - delta_diff;
+			effective_width = delta_diff > 0 ? new_width : effective_width;
+			if (effective_width <= 0) goto next_line;
+		}
 
 		switch (mode) {
-			default: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - (delta_diff & ~1);
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
-					}
-
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width / 2; x > 0; x--) {
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-							ALPHA_BLEND_2();
-							_mm_storel_epi64((__m128i*) dst, srcABCD);
-							src += 2;
-							dst += 2;
-						}
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							__m128i srcABCD = _mm_cvtsi32_si128(src->data);
-							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-							ALPHA_BLEND_2();
-							dst->data = _mm_cvtsi128_si32(srcABCD);
-						}
-						break;
-					}
+			default:
+				for (uint x = (uint) effective_width / 2; x > 0; x--) {
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
+					ALPHA_BLEND_2();
+					_mm_storel_epi64((__m128i*) dst, srcABCD);
+					src += 2;
+					dst += 2;
+				}
 
-					default: NOT_REACHED();
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
+					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+					ALPHA_BLEND_2();
+					dst->data = _mm_cvtsi128_si32(srcABCD);
 				}
 				break;
-			}
 
-			case BM_COLOUR_REMAP: {
-				switch (read_mode) {
-					case RM_WITH_MARGIN: {
-						src += src_rgba_line[0].data;
-						src_mv += src_rgba_line[0].data;
-						dst += src_rgba_line[0].data;
-						const int width_diff = si->sprite_width - bp->width;
-						effective_width = bp->width - (int) src_rgba_line[0].data;
-						const int delta_diff = (int) src_rgba_line[1].data - width_diff;
-						const int new_width = effective_width - delta_diff;
-						effective_width = delta_diff > 0 ? new_width : effective_width;
-						if (effective_width <= 0) break;
-						/* FALLTHROUGH */
+			case BM_COLOUR_REMAP:
+				for (uint x = (uint) effective_width / 2; x > 0; x--) {
+					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
+					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
+					uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
+
+					/* Remap colours. */
+					if (mvX2 & 0x00FF00FF) {
+						/* Written so the compiler uses CMOV. */
+						const Colour src0 = src[0];
+						const uint m0 = (byte) mvX2;
+						const uint r0 = remap[m0];
+						const Colour c0map = (this->LookupColourInPalette(r0).data & 0x00FFFFFF) | (src0.data & 0xFF000000);
+						Colour c0 = 0; // Use alpha of 0 to keep dst as is.
+						c0 = r0 == 0 ? c0 : c0map;
+						c0 = m0 != 0 ? c0 : src0;
+						srcABCD = _mm_cvtsi32_si128(c0.data);
+
+						const Colour src1 = src[1];
+						const uint m1 = (byte) (mvX2 >> 16);
+						const uint r1 = remap[m1];
+						const Colour c1map = (this->LookupColourInPalette(r1).data & 0x00FFFFFF) | (src1.data & 0xFF000000);
+						Colour c1 = 0;
+						c1 = r1 == 0 ? c1 : c1map;
+						c1 = m1 != 0 ? c1 : src1;
+						INSR32(c1.data, srcABCD, 1);
+
+						if ((mvX2 & 0xFF00FF00) != 0x80008000) {
+							ADJUST_BRIGHTNESS_2(srcABCD, mvX2);
+						}
 					}
 
-					case RM_WITH_SKIP: {
-						for (uint x = (uint) effective_width / 2; x > 0; x--) {
-							__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
-							__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-							uint32 mvX2 = *((uint32 *) const_cast<MapValue *>(src_mv));
-
-							/* Remap colours. */
-							if (mvX2 & 0x00FF00FF) {
-								/* Written so the compiler uses CMOV. */
-								const Colour src0 = src[0];
-								const uint m0 = (byte) mvX2;
-								const uint r0 = remap[m0];
-								const Colour c0map = (this->LookupColourInPalette(r0).data & 0x00FFFFFF) | (src0.data & 0xFF000000);
-								Colour c0 = 0; // Use alpha of 0 to keep dst as is.
-								c0 = r0 == 0 ? c0 : c0map;
-								c0 = m0 != 0 ? c0 : src0;
-								srcABCD = _mm_cvtsi32_si128(c0.data);
-
-								const Colour src1 = src[1];
-								const uint m1 = (byte) (mvX2 >> 16);
-								const uint r1 = remap[m1];
-								const Colour c1map = (this->LookupColourInPalette(r1).data & 0x00FFFFFF) | (src1.data & 0xFF000000);
-								Colour c1 = 0;
-								c1 = r1 == 0 ? c1 : c1map;
-								c1 = m1 != 0 ? c1 : src1;
-								INSR32(c1.data, srcABCD, 1);
-
-								if ((mvX2 & 0xFF00FF00) != 0x80008000) {
-									ADJUST_BRIGHTNESS_2(srcABCD, mvX2);
-								}
-							}
-
-							/* Blend colours. */
-							ALPHA_BLEND_2();
-							_mm_storel_epi64((__m128i *) dst, srcABCD);
-							dst += 2;
-							src += 2;
-							src_mv += 2;
-						}
+					/* Blend colours. */
+					ALPHA_BLEND_2();
+					_mm_storel_epi64((__m128i *) dst, srcABCD);
+					dst += 2;
+					src += 2;
+					src_mv += 2;
+				}
 
-						if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
-							/* In case the m-channel is zero, do not remap this pixel in any way. */
-							__m128i srcABCD;
-							if (src_mv->m) {
-								const uint r = remap[src_mv->m];
-								if (r != 0) {
-									Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
-									if (src->a == 255) {
-										*dst = remapped_colour;
-									} else {
-										remapped_colour.a = src->a;
-										srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
-										goto bmcr_alpha_blend_single;
-									}
-								}
+				if ((bt_last == BT_NONE && effective_width & 1) || bt_last == BT_ODD) {
+					/* In case the m-channel is zero, do not remap this pixel in any way. */
+					__m128i srcABCD;
+					if (src_mv->m) {
+						const uint r = remap[src_mv->m];
+						if (r != 0) {
+							Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
+							if (src->a == 255) {
+								*dst = remapped_colour;
 							} else {
-								srcABCD = _mm_cvtsi32_si128(src->data);
-								if (src->a < 255) {
-bmcr_alpha_blend_single:
-									__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-									ALPHA_BLEND_2();
-								}
-								dst->data = _mm_cvtsi128_si32(srcABCD);
+								remapped_colour.a = src->a;
+								srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
+								goto bmcr_alpha_blend_single;
 							}
 						}
-						break;
+					} else {
+						srcABCD = _mm_cvtsi32_si128(src->data);
+						if (src->a < 255) {
+bmcr_alpha_blend_single:
+							__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
+							ALPHA_BLEND_2();
+						}
+						dst->data = _mm_cvtsi128_si32(srcABCD);
 					}
-
-					default: NOT_REACHED();
 				}
-				src_mv_line += si->sprite_width;
 				break;
-			}
 
-			case BM_TRANSPARENT: {
+			case BM_TRANSPARENT:
 				/* Make the current colour a bit more black, so it looks like this image is transparent. */
 				for (uint x = (uint) bp->width / 2; x > 0; x--) {
 					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
@@ -197,6 +169,7 @@ bmcr_alpha_blend_single:
 					src += 2;
 					dst += 2;
 				}
+
 				if ((bt_last == BT_NONE && bp->width & 1) || bt_last == BT_ODD) {
 					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
 					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
@@ -204,9 +177,10 @@ bmcr_alpha_blend_single:
 					dst->data = _mm_cvtsi128_si32(dstAB);
 				}
 				break;
-			}
 		}
 
+next_line:
+		if (mode == BM_COLOUR_REMAP) src_mv_line += si->sprite_width;
 		src_rgba_line = (const Colour*) ((const byte*) src_rgba_line + si->sprite_line_size);
 		dst_line += bp->pitch;
 	}
@@ -224,19 +198,15 @@ void Blitter_32bppSSSE3::Draw(Blitter::BlitterParams *bp, BlitterMode mode, Zoom
 {
 	switch (mode) {
 		case BM_NORMAL: {
-			const BlockType bt_last = (BlockType) (bp->width & 1);
 			if (bp->skip_left != 0 || bp->width <= MARGIN_NORMAL_THRESHOLD) {
+				const BlockType bt_last = (BlockType) (bp->width & 1);
 				switch (bt_last) {
 					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_SKIP, BT_EVEN>(bp, zoom); return;
 					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_SKIP, BT_ODD>(bp, zoom); return;
 					default: NOT_REACHED();
 				}
 			} else {
-				switch (bt_last) {
-					case BT_EVEN: Draw<BM_NORMAL, RM_WITH_MARGIN, BT_EVEN>(bp, zoom); return;
-					case BT_ODD:  Draw<BM_NORMAL, RM_WITH_MARGIN, BT_ODD>(bp, zoom); return;
-					default: NOT_REACHED();
-				}
+				Draw<BM_NORMAL, RM_WITH_MARGIN, BT_NONE>(bp, zoom); return;
 			}
 			break;
 		}