gpu_unai: add 4bpp asm sprite blitter

1 files changed, 55 insertions, 0 deletions

diff --git a/plugins/gpu_unai/gpu_arm.s b/plugins/gpu_unai/gpu_arm.s
new file mode 100644
index 0000000..a2fa174
--- /dev/null
+++ b/plugins/gpu_unai/gpu_arm.s
@@ -0,0 +1,55 @@
+/*
+ * (C) Gražvydas "notaz" Ignotas, 2011
+ *
+ * This work is licensed under the terms of  GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+
+.text
+.align 2
+
+@ in: r0=dst, r2=pal, r12=0x1e
+@ trashes r6-r8,lr,flags
+.macro do_4_pixels rs ibase obase
+.if \ibase - 1 < 0
+    and     r6, r12, \rs, lsl #1
+.else
+    and     r6, r12, \rs, lsr #\ibase-1
+.endif
+    and     r7, r12, \rs, lsr #\ibase+3
+    and     r8, r12, \rs, lsr #\ibase+7
+    and     lr, r12, \rs, lsr #\ibase+11
+    ldrh    r6, [r2, r6]
+    ldrh    r7, [r2, r7]
+    ldrh    r8, [r2, r8]
+    ldrh    lr, [r2, lr]
+    tst     r6, r6
+    strneh  r6, [r0, #\obase+0]
+    tst     r7, r7
+    strneh  r7, [r0, #\obase+2]
+    tst     r8, r8
+    strneh  r8, [r0, #\obase+4]
+    tst     lr, lr
+    strneh  lr, [r0, #\obase+6]
+.endm
+
+.global draw_spr16_full @ (u16 *d, void *s, u16 *pal, int lines)
+draw_spr16_full:
+    stmfd   sp!, {r4-r8,lr}
+    mov     r12, #0x1e             @ empty pixel
+
+0:
+    ldmia   r1, {r4,r5}
+    do_4_pixels r4, 0,  0
+    do_4_pixels r4, 16, 8
+    do_4_pixels r5, 0,  16
+    do_4_pixels r5, 16, 24
+    subs    r3, #1
+    add     r0, #2048
+    add     r1, #2048
+    bgt     0b
+
+    ldmfd   sp!, {r4-r8,pc}
+
+@ vim:filetype=armasm