HAM decode cleanup and 1 pixel early start fix.

diff --git a/drawing.cpp b/drawing.cpp
index fd4ae1bae77e603de16d626c02c0fffa8d6f0aad..6a3702a12c725e768235dc67d405c356330ece6a 100644 (file)
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -2620,180 +2620,105 @@ static void dummy_worker (int start, int stop, int blank)
 }
 
 static int ham_decode_pixel;
-static unsigned int ham_lastcolor;
-static bool ham_decode_start;
+static uae_u32 ham_lastcolor;
 
-/* Decode HAM in the invisible portion of the display (left of VISIBLE_LEFT_BORDER),
- * but don't draw anything in.  This is done to prepare HAM_LASTCOLOR for later,
- * when decode_ham runs.
- *
- */
-static void init_ham_decoding(void)
+static void decode_ham_pixel(int hdp)
 {
-       int unpainted_amiga = unpainted + hamleftborderhidden;
-
-       ham_decode_pixel = src_pixel - hamleftborderhidden;
-       ham_lastcolor = color_reg_get(&colors_for_drawing, 0);
-
        if (!bplham) {
-               if (unpainted_amiga > 0) {
-                       int pv = pixdata.apixels[ham_decode_pixel + unpainted_amiga - 1];
+               int pv = pixdata.apixels[hdp];
 #ifdef AGA
-                       if (aga_mode)
-                               ham_lastcolor = colors_for_drawing.color_regs_aga[pv ^ bplxor] & 0xffffff;
-                       else
+               if (aga_mode)
+                       ham_lastcolor = colors_for_drawing.color_regs_aga[pv ^ bplxor] & 0xffffff;
+               else
 #endif
-                               ham_lastcolor = colors_for_drawing.color_regs_ecs[pv] & 0xfff;
-               }
-#ifdef AGA
+                       ham_lastcolor = colors_for_drawing.color_regs_ecs[pv] & 0xfff;
        } else if (aga_mode) {
                if (bplplanecnt >= 7) { /* AGA mode HAM8 */
-                       while (unpainted_amiga-- > 0) {
-                               int pw = pixdata.apixels[ham_decode_pixel++];
-                               int pv = pw ^ bplxor;
-                               int pc = pv >> 2;
-                               switch (pv & 0x3)
-                               {
+                       int pw = pixdata.apixels[hdp];
+                       int pv = pw ^ bplxor;
+                       int pc = pv >> 2;
+                       switch (pv & 0x3)
+                       {
                                case 0x0: ham_lastcolor = colors_for_drawing.color_regs_aga[pc] & 0xffffff; break;
                                case 0x1: ham_lastcolor &= 0xFFFF03; ham_lastcolor |= (pw & 0xFC); break;
                                case 0x2: ham_lastcolor &= 0x03FFFF; ham_lastcolor |= (pw & 0xFC) << 16; break;
                                case 0x3: ham_lastcolor &= 0xFF03FF; ham_lastcolor |= (pw & 0xFC) << 8; break;
-                               }
                        }
                } else { /* AGA mode HAM6 */
-                       while (unpainted_amiga-- > 0) {
-                               int pw = pixdata.apixels[ham_decode_pixel++];
-                               int pv = pw ^ bplxor;
-                               uae_u32 pc = ((pw & 0xf) << 0) | ((pw & 0xf) << 4);
-                               switch (pv & 0x30)
-                               {
+                       int pw = pixdata.apixels[hdp];
+                       int pv = pw ^ bplxor;
+                       uae_u32 pc = ((pw & 0xf) << 0) | ((pw & 0xf) << 4);
+                       switch (pv & 0x30)
+                       {
                                case 0x00: ham_lastcolor = colors_for_drawing.color_regs_aga[pv & 0x0f] & 0xffffff; break;
                                case 0x10: ham_lastcolor &= 0xFFFF00; ham_lastcolor |= pc << 0; break;
                                case 0x20: ham_lastcolor &= 0x00FFFF; ham_lastcolor |= pc << 16; break;
                                case 0x30: ham_lastcolor &= 0xFF00FF; ham_lastcolor |= pc << 8; break;
-                               }
                        }
                }
-#endif
        } else {
                if (!bpldualpf) {
                        /* OCS/ECS mode HAM6 */
-                       while (unpainted_amiga-- > 0) {
-                               int pv = pixdata.apixels[ham_decode_pixel++];
-                               switch (pv & 0x30)
-                               {
+                       int pv = pixdata.apixels[ham_decode_pixel];
+                       switch (pv & 0x30)
+                       {
                                case 0x00: ham_lastcolor = colors_for_drawing.color_regs_ecs[pv] & 0xfff; break;
                                case 0x10: ham_lastcolor &= 0xFF0; ham_lastcolor |= (pv & 0xF); break;
                                case 0x20: ham_lastcolor &= 0x0FF; ham_lastcolor |= (pv & 0xF) << 8; break;
                                case 0x30: ham_lastcolor &= 0xF0F; ham_lastcolor |= (pv & 0xF) << 4; break;
-                               }
                        }
                } else {
                        /* OCS/ECS mode HAM6 + DPF */
-                       while (unpainted_amiga-- > 0) {
-                               int pv = pixdata.apixels[ham_decode_pixel++];
-                               int *lookup = bpldualpfpri ? dblpf_ind2 : dblpf_ind1;
-                               int idx = lookup[pv];
-                               switch (pv & 0x30)
-                               {
+                       int pv = pixdata.apixels[ham_decode_pixel];
+                       int *lookup = bpldualpfpri ? dblpf_ind2 : dblpf_ind1;
+                       int idx = lookup[pv];
+                       switch (pv & 0x30)
+                       {
                                case 0x00: ham_lastcolor = colors_for_drawing.color_regs_ecs[idx] & 0xfff; break;
                                case 0x10: ham_lastcolor &= 0xFF0; ham_lastcolor |= (idx & 0xF); break;
                                case 0x20: ham_lastcolor &= 0x0FF; ham_lastcolor |= (idx & 0xF) << 8; break;
                                case 0x30: ham_lastcolor &= 0xF0F; ham_lastcolor |= (idx & 0xF) << 4; break;
-                               }
                        }
                }
        }
+}
+
+
+/* Decode HAM in the invisible portion of the display (left of VISIBLE_LEFT_BORDER),
+ * but don't draw anything in.  This is done to prepare HAM_LASTCOLOR for later,
+ * when decode_ham runs.
+ *
+ */
+static void init_ham_decoding(void)
+{
+       int unpainted_amiga = unpainted;
 
-       ham_decode_start = true;
+       ham_decode_pixel = src_pixel - hamleftborderhidden;
+       ham_lastcolor = color_reg_get(&colors_for_drawing, 0);
+       while (unpainted_amiga-- > 0) {
+               decode_ham_pixel(ham_decode_pixel++);
+       }
 }
 
 static void decode_ham(int pix, int stoppos, int blank)
 {
        int todraw_amiga = res_shift_from_window(stoppos - pix);
-
-       if (ham_decode_start) {
-               // first HAM decoding in scanline: start from previous pixel
-               todraw_amiga++;
-               ham_decode_pixel--;
-               ham_decode_start = false;
+       while (todraw_amiga-- > 0) {
+               decode_ham_pixel(ham_decode_pixel);
+               ham_linebuf[ham_decode_pixel++] = ham_lastcolor;
        }
+}
 
-       if (!bplham) {
-               while (todraw_amiga-- > 0) {
-                       int pv = pixdata.apixels[ham_decode_pixel];
-#ifdef AGA
-                       if (aga_mode)
-                               ham_lastcolor = colors_for_drawing.color_regs_aga[pv ^ bplxor] & 0xffffff;
-                       else
-#endif
-                               ham_lastcolor = colors_for_drawing.color_regs_ecs[pv] & 0xfff;
-
-                       ham_linebuf[ham_decode_pixel++] = ham_lastcolor;
-               }
-#ifdef AGA
-       } else if (aga_mode) {
-               if (bplplanecnt >= 7) { /* AGA mode HAM8 */
-                       while (todraw_amiga-- > 0) {
-                               int pw = pixdata.apixels[ham_decode_pixel];
-                               int pv = pw ^ bplxor;
-                               int pc = pv >> 2;
-                               switch (pv & 0x3)
-                               {
-                               case 0x0: ham_lastcolor = colors_for_drawing.color_regs_aga[pc] & 0xffffff; break;
-                               case 0x1: ham_lastcolor &= 0xFFFF03; ham_lastcolor |= (pw & 0xFC); break;
-                               case 0x2: ham_lastcolor &= 0x03FFFF; ham_lastcolor |= (pw & 0xFC) << 16; break;
-                               case 0x3: ham_lastcolor &= 0xFF03FF; ham_lastcolor |= (pw & 0xFC) << 8; break;
-                               }
-                               ham_linebuf[ham_decode_pixel++] = ham_lastcolor;
-                       }
-               } else { /* AGA mode HAM6 */
-                       while (todraw_amiga-- > 0) {
-                               int pw = pixdata.apixels[ham_decode_pixel];
-                               int pv = pw ^ bplxor;
-                               uae_u32 pc = ((pw & 0xf) << 0) | ((pw & 0xf) << 4);
-                               switch (pv & 0x30)
-                               {
-                               case 0x00: ham_lastcolor = colors_for_drawing.color_regs_aga[pv & 0x0f] & 0xffffff; break;
-                               case 0x10: ham_lastcolor &= 0xFFFF00; ham_lastcolor |= pc << 0; break;
-                               case 0x20: ham_lastcolor &= 0x00FFFF; ham_lastcolor |= pc << 16; break;
-                               case 0x30: ham_lastcolor &= 0xFF00FF; ham_lastcolor |= pc << 8; break;
-                               }
-                               ham_linebuf[ham_decode_pixel++] = ham_lastcolor;
-                       }
-               }
-#endif
-       } else {
-               if (!bpldualpf) {
-                       /* OCS/ECS mode HAM6 */
-                       while (todraw_amiga-- > 0) {
-                               int pv = pixdata.apixels[ham_decode_pixel];
-                               switch (pv & 0x30)
-                               {
-                               case 0x00: ham_lastcolor = colors_for_drawing.color_regs_ecs[pv] & 0xfff; break;
-                               case 0x10: ham_lastcolor &= 0xFF0; ham_lastcolor |= (pv & 0xF); break;
-                               case 0x20: ham_lastcolor &= 0x0FF; ham_lastcolor |= (pv & 0xF) << 8; break;
-                               case 0x30: ham_lastcolor &= 0xF0F; ham_lastcolor |= (pv & 0xF) << 4; break;
-                               }
-                               ham_linebuf[ham_decode_pixel++] = ham_lastcolor;
-                       }
-               } else {
-                       /* OCS/ECS mode HAM6 + DPF */
-                       while (todraw_amiga-- > 0) {
-                               int pv = pixdata.apixels[ham_decode_pixel];
-                               int *lookup = bpldualpfpri ? dblpf_ind2 : dblpf_ind1;
-                               int idx = lookup[pv];
-                               switch (pv & 0x30)
-                               {
-                               case 0x00: ham_lastcolor = colors_for_drawing.color_regs_ecs[idx] & 0xfff; break;
-                               case 0x10: ham_lastcolor &= 0xFF0; ham_lastcolor |= (idx & 0xF); break;
-                               case 0x20: ham_lastcolor &= 0x0FF; ham_lastcolor |= (idx & 0xF) << 8; break;
-                               case 0x30: ham_lastcolor &= 0xF0F; ham_lastcolor |= (idx & 0xF) << 4; break;
-                               }
-                               ham_linebuf[ham_decode_pixel++] = ham_lastcolor;
-                       }
-               }
+static void decode_ham_border(int pix, int stoppos, int blank)
+{
+       ham_lastcolor = color_reg_get(&colors_for_drawing, 0);
+       if (pix >= stoppos) {
+               return;
        }
+       // HAM decoding starts 1 pixel early
+       int todraw_amiga = res_shift_from_window(stoppos - pix) - 1;
+       int hdp = ham_decode_pixel + todraw_amiga;
+       decode_ham_pixel(hdp);
 }
 
 static void erase_ham_right_border(int pix, int stoppos, bool blank)
@@ -3912,7 +3837,7 @@ static void pfield_draw_line(struct vidbuffer *vb, int lineno, int gfx_ypos, int
                        uae_u16 fm = dp_for_drawing->fmode;
                        init_ham_decoding();
                        int oham_decode_pixel = ham_decode_pixel;
-                       do_color_changes(dummy_worker, decode_ham, lineno);
+                       do_color_changes(decode_ham_border, decode_ham, lineno);
                        if (have_color_changes) {
                                // do_color_changes() did color changes and register changes, restore them.
                                adjust_drawing_colors(dp_for_drawing->ctable, -1, false);