rename gpu_senquack to gpu_unai

[pcsx_rearmed.git] / plugins / gpu_unai / gpu_inner_blend_arm.h

diff --git a/plugins/gpu_unai/gpu_inner_blend_arm.h b/plugins/gpu_unai/gpu_inner_blend_arm.h
new file mode 100644 (file)
index 0000000..6413527
--- /dev/null
+++ b/plugins/gpu_unai/gpu_inner_blend_arm.h
@@ -0,0 +1,103 @@
+#ifndef _OP_BLEND_ARM_H_
+#define _OP_BLEND_ARM_H_
+
+////////////////////////////////////////////////////////////////////////////////
+// Blend bgr555 color in 'uSrc' (foreground) with bgr555 color
+//  in 'uDst' (background), returning resulting color.
+//
+// INPUT:
+//  'uSrc','uDst' input: -bbbbbgggggrrrrr
+//                       ^ bit 16
+// OUTPUT:
+//           u16 output: 0bbbbbgggggrrrrr
+//                       ^ bit 16
+// RETURNS:
+// Where '0' is zero-padding, and '-' is don't care
+////////////////////////////////////////////////////////////////////////////////
+template <int BLENDMODE, bool SKIP_USRC_MSB_MASK>
+GPU_INLINE uint_fast16_t gpuBlendingARM(uint_fast16_t uSrc, uint_fast16_t uDst)
+{
+       // These use Blargg's bitwise modulo-clamping:
+       //  http://blargg.8bitalley.com/info/rgb_mixing.html
+       //  http://blargg.8bitalley.com/info/rgb_clamped_add.html
+       //  http://blargg.8bitalley.com/info/rgb_clamped_sub.html
+
+       uint_fast16_t mix;
+
+       // Clear preserved msb
+       asm ("bic %[uDst], %[uDst], #0x8000" : [uDst] "+r" (uDst));
+
+       if (BLENDMODE == 3) {
+               // Prepare uSrc for blending ((0.25 * uSrc) & (0.25 * mask))
+               asm ("and %[uSrc], %[mask], %[uSrc], lsr #0x2" : [uSrc] "+r" (uSrc) : [mask] "r" (0x1ce7));
+       } else if (!SKIP_USRC_MSB_MASK) {
+               asm ("bic %[uSrc], %[uSrc], #0x8000" : [uSrc] "+r" (uSrc));
+       }
+
+
+       // 0.5 x Back + 0.5 x Forward
+       if (BLENDMODE==0) {
+               // mix = ((uSrc + uDst) - ((uSrc ^ uDst) & 0x0421)) >> 1;
+               asm ("eor %[mix], %[uSrc], %[uDst]\n\t" // uSrc ^ uDst
+                    "and %[mix], %[mix], %[mask]\n\t"  // ... & 0x0421
+                    "sub %[mix], %[uDst], %[mix]\n\t"  // uDst - ...
+                    "add %[mix], %[uSrc], %[mix]\n\t"  // uSrc + ...
+                    "mov %[mix], %[mix], lsr #0x1\n\t" // ... >> 1
+                    : [mix] "=&r" (mix)
+                    : [uSrc] "r" (uSrc), [uDst] "r" (uDst), [mask] "r" (0x0421));
+       }
+
+       if (BLENDMODE == 1 || BLENDMODE == 3) {
+               // u32 sum      = uSrc + uDst;
+               // u32 low_bits = (uSrc ^ uDst) & 0x0421;
+               // u32 carries  = (sum - low_bits) & 0x8420;
+               // u32 modulo   = sum - carries;
+               // u32 clamp    = carries - (carries >> 5);
+               // mix = modulo | clamp;
+
+               u32 sum;
+
+               asm ("add %[sum], %[uSrc], %[uDst]\n\t" // sum = uSrc + uDst
+                    "eor %[mix], %[uSrc], %[uDst]\n\t" // uSrc ^ uDst
+                    "and %[mix], %[mix], %[mask]\n\t"  // low_bits = (... & 0x0421)
+                    "sub %[mix], %[sum], %[mix]\n\t"   // sum - low_bits
+                    "and %[mix], %[mix], %[mask], lsl #0x05\n\t"  // carries = ... & 0x8420
+                    "sub %[sum], %[sum], %[mix] \n\t"  // modulo = sum - carries
+                    "sub %[mix], %[mix], %[mix], lsr #0x05\n\t" // clamp = carries - (carries >> 5)
+                    "orr %[mix], %[sum], %[mix]"       // mix = modulo | clamp
+                    : [sum] "=&r" (sum), [mix] "=&r" (mix)
+                    : [uSrc] "r" (uSrc), [uDst] "r" (uDst), [mask] "r" (0x0421));
+       }
+    
+       // 1.0 x Back - 1.0 x Forward
+       if (BLENDMODE==2) {
+               u32 diff;
+               // u32 diff     = uDst - uSrc + 0x8420;
+               // u32 low_bits = (uDst ^ uSrc) & 0x8420;
+               // u32 borrows  = (diff - low_bits) & 0x8420;
+               // u32 modulo   = diff - borrows;
+               // u32 clamp    = borrows - (borrows >> 5);
+               // mix = modulo & clamp;
+               asm ("sub %[diff], %[uDst], %[uSrc]\n\t"  // uDst - uSrc
+                    "add %[diff], %[diff], %[mask]\n\t"  // diff = ... + 0x8420
+                    "eor %[mix], %[uDst], %[uSrc]\n\t"   // uDst ^ uSrc
+                    "and %[mix], %[mix], %[mask]\n\t"    // low_bits = ... & 0x8420
+                    "sub %[mix], %[diff], %[mix]\n\t"    // diff - low_bits
+                    "and %[mix], %[mix], %[mask]\n\t"    // borrows = ... & 0x8420
+                    "sub %[diff], %[diff], %[mix]\n\t"   // modulo = diff - borrows
+                    "sub %[mix], %[mix], %[mix], lsr #0x05\n\t"  // clamp = borrows - (borrows >> 5)
+                    "and %[mix], %[diff], %[mix]"        // mix = modulo & clamp
+                    : [diff] "=&r" (diff), [mix] "=&r" (mix)
+                    : [uSrc] "r" (uSrc), [uDst] "r" (uDst), [mask] "r" (0x8420));
+       }
+
+       // There's not a case where we can get into this function,
+       // SKIP_USRC_MSB_MASK is false, and the msb of uSrc is unset.
+       if (!SKIP_USRC_MSB_MASK) {
+               asm ("orr %[mix], %[mix], #0x8000" : [mix] "+r" (mix));
+       }
+  
+       return mix;
+}
+
+#endif  //_OP_BLEND_ARM_H_