357 lines
9.9 KiB
NASM
357 lines
9.9 KiB
NASM
; overlay routines
|
|
|
|
; fill a whole overlay with a color
|
|
; inputs:
|
|
; r0: color
|
|
; r1: overlay number
|
|
; outputs:
|
|
; none
|
|
fill_overlay:
|
|
push r1
|
|
push r2
|
|
push r3
|
|
push r31
|
|
|
|
mov r2, r1
|
|
or r2, 0x80000100 ; bitwise or the overlay number with the command to get the overlay size
|
|
or r1, 0x80000200 ; bitwise or the overlay number with the command to get the framebuffer pointer
|
|
in r1, r1 ; r1: overlay framebuffer poiner
|
|
in r2, r2
|
|
mov r3, r2
|
|
and r2, 0x0000FFFF ; r2: X size
|
|
sra r3, 16 ; r3: Y size
|
|
mul r2, r3
|
|
mov r31, r2
|
|
fill_overlay_loop:
|
|
mov [r1], r0
|
|
add r1, 4
|
|
loop fill_overlay_loop
|
|
|
|
pop r31
|
|
pop r3
|
|
pop r2
|
|
pop r1
|
|
ret
|
|
|
|
; draw a filled rectangle to an overlay
|
|
; inputs:
|
|
; r0: X coordinate of top-left
|
|
; r1: Y coordinate of top-left
|
|
; r2: X size
|
|
; r3: Y size
|
|
; r4: color
|
|
; r5: overlay number
|
|
; outputs:
|
|
; none
|
|
draw_filled_rectangle_to_overlay:
|
|
push r0
|
|
push r1
|
|
push r2
|
|
push r3
|
|
push r4
|
|
push r5
|
|
push r6
|
|
push r7
|
|
|
|
; calculate pointer to the framebuffer
|
|
mov r6, r5 ; r6: overlay number
|
|
or r6, 0x80000100 ; bitwise or the overlay number with the command to get the overlay size
|
|
in r7, r6
|
|
and r7, 0x0000FFFF ; mask off the height, we only need the width
|
|
mul r7, 4 ; r7: overlay width in bytes (width * 4)
|
|
mul r1, r7 ; y * width * 4
|
|
mul r0, 4 ; x * 4
|
|
add r0, r1 ; y * width * 4 + (x * 4)
|
|
or r5, 0x80000200 ; bitwise or the overlay number with the command to get the framebuffer pointer
|
|
in r5, r5
|
|
add r0, r5 ; r0: pointer to framebuffer
|
|
|
|
mov r6, r2
|
|
mul r6, 4 ; multiply the X size by 4, since 4 bytes per pixel
|
|
|
|
draw_filled_rectangle_to_overlay_y_loop:
|
|
mov r5, r2 ; x counter
|
|
draw_filled_rectangle_to_overlay_x_loop:
|
|
mov [r0], r4
|
|
add r0, 4 ; increment framebuffer pointer
|
|
dec r5
|
|
ifnz jmp draw_filled_rectangle_to_overlay_x_loop ; loop if there are still more X pixels to draw
|
|
|
|
sub r0, r6 ; return to the beginning of this line
|
|
add r0, r7 ; increment to the next line
|
|
dec r3
|
|
ifnz jmp draw_filled_rectangle_to_overlay_y_loop ; loop if there are still more Y pixels to draw
|
|
|
|
pop r7
|
|
pop r6
|
|
pop r5
|
|
pop r4
|
|
pop r3
|
|
pop r2
|
|
pop r1
|
|
pop r0
|
|
ret
|
|
|
|
; draw a single font tile to an overlay
|
|
; inputs:
|
|
; r0: tile number
|
|
; r1: X coordinate
|
|
; r2: Y coordinate
|
|
; r3: foreground color
|
|
; r4: background color
|
|
; r5: overlay number
|
|
; outputs:
|
|
; none
|
|
draw_font_tile_to_overlay:
|
|
push r0
|
|
push r1
|
|
push r2
|
|
push r5
|
|
push r6
|
|
push r7
|
|
|
|
;movz.8 r0, r0 ; ensure the tile number is a single byte
|
|
|
|
; calculate pointer to the tile data
|
|
push r1
|
|
push r2
|
|
mov r1, 8 ; tile width
|
|
mov r2, 16 ; tile height
|
|
mul r1, r2
|
|
mul r0, r1
|
|
mul r0, 4 ; 4 bytes per pixel
|
|
add r0, font ; r0: pointer to tile data
|
|
pop r2
|
|
pop r1
|
|
|
|
; calculate pointer to the framebuffer
|
|
mov r7, r5 ; r7: overlay number
|
|
or r7, 0x80000100 ; bitwise or the overlay number with the command to get the overlay size
|
|
in r6, r7
|
|
and r6, 0x0000FFFF ; mask off the height, we only need the width
|
|
mul r6, 4 ; 4 bytes per pixel
|
|
mov r7, r6 ; r7: overlay width in bytes (width * 4)
|
|
mul r2, r7 ; y * width * 4
|
|
mul r1, 4 ; x * 4
|
|
add r1, r2 ; y * width * 4 + (x * 4)
|
|
or r5, 0x80000200 ; bitwise or the overlay number with the command to get the framebuffer pointer
|
|
in r6, r5
|
|
add r1, r6 ; r1: pointer to framebuffer
|
|
|
|
mov r6, 16 ; y counter
|
|
draw_font_tile_to_overlay_y_loop:
|
|
mov r5, 8 ; x counter
|
|
draw_font_tile_to_overlay_x_loop:
|
|
mov r2, [r0]
|
|
cmp r2, 0xFF000000
|
|
ifz jmp draw_font_tile_to_overlay_x_loop_background
|
|
; drawing foreground pixel
|
|
cmp r3, 0x00000000 ; is the foreground color supposed to be transparent?
|
|
ifz jmp draw_font_tile_to_overlay_x_loop_end
|
|
mov [r1], r3 ; draw foreground color
|
|
jmp draw_font_tile_to_overlay_x_loop_end
|
|
draw_font_tile_to_overlay_x_loop_background:
|
|
; drawing background pixel
|
|
cmp r4, 0x00000000 ; is the background color supposed to be transparent?
|
|
ifz jmp draw_font_tile_to_background_x_loop_end
|
|
mov [r1], r4 ; draw background color
|
|
draw_font_tile_to_overlay_x_loop_end:
|
|
add r0, 4 ; increment tile pointer
|
|
add r1, 4 ; increment framebuffer pointer
|
|
dec r5
|
|
ifnz jmp draw_font_tile_to_overlay_x_loop ; loop if there are still more X pixels to draw
|
|
sub r1, 32 ; 8*4, return to the beginning of this line
|
|
add r1, r7 ; increment to the next line by adding the overlay width in bytes
|
|
dec r6
|
|
ifnz jmp draw_font_tile_to_overlay_y_loop ; loop if there are still more Y pixels to draw
|
|
|
|
pop r7
|
|
pop r6
|
|
pop r5
|
|
pop r2
|
|
pop r1
|
|
pop r0
|
|
ret
|
|
|
|
; draw text on an overlay
|
|
; inputs:
|
|
; r0: pointer to null-terminated string
|
|
; r1: X coordinate
|
|
; r2: Y coordinate
|
|
; r3: foreground color
|
|
; r4: background color
|
|
; r5: overlay number
|
|
; outputs:
|
|
; r1: X coordinate of end of text
|
|
draw_str_to_overlay:
|
|
push r0
|
|
push r6
|
|
mov r6, r0
|
|
draw_str_to_overlay_loop:
|
|
movz.8 r0, [r6]
|
|
call draw_font_tile_to_overlay
|
|
inc r6
|
|
add r1, 8
|
|
cmp.8 [r6], 0x00
|
|
ifnz jmp draw_str_to_overlay_loop
|
|
pop r6
|
|
pop r0
|
|
ret
|
|
|
|
; finds the overlay with the highest priority covering the specified position
|
|
; does not check overlay 31, which is always the mouse pointer
|
|
; inputs:
|
|
; r0: X coordinate
|
|
; r1: Y coordinate
|
|
; outputs:
|
|
; r0: overlay number
|
|
find_overlay_covering_position:
|
|
; TODO:
|
|
|
|
; checks if the specified overlay is covering the specified position on screen
|
|
; the overlay can be enabled or disabled
|
|
; example:
|
|
; overlay 0 is at (0,0) and is 32x32 in size
|
|
; point (4,2) is covered by overlay 0
|
|
; point (16,16) is covered by overlay 0
|
|
; point (31,31) is covered by overlay 0
|
|
; point (32,32) is NOT covered by overlay 0, because it is outside of the overlay's area
|
|
; this works for overlays of any size, at any position on screen
|
|
; inputs:
|
|
; r0: X coordinate
|
|
; r1: Y coordinate
|
|
; r2: overlay number
|
|
; outputs:
|
|
; Z flag: set if covering, clear if not covering
|
|
check_if_overlay_covers_position:
|
|
push r0
|
|
push r1
|
|
push r3
|
|
push r4
|
|
push r5
|
|
push r6
|
|
push r7
|
|
|
|
mov r3, r2
|
|
or r3, 0x80000000 ; bitwise or the overlay number with the command to get the overlay position
|
|
in r4, r3
|
|
mov r5, r4
|
|
and r4, 0x0000FFFF ; r4: X position
|
|
sra r5, 16 ; r5: Y position
|
|
|
|
mov r3, r2
|
|
or r3, 0x80000100 ; bitwise or the overlay number with the command to get the overlay size
|
|
in r6, r3
|
|
mov r7, r6
|
|
and r6, 0x0000FFFF ; r6: width
|
|
sra r7, 16 ; r7: height
|
|
|
|
add r6, r4
|
|
add r7, r5
|
|
|
|
; (r4,r5): coordinates of top-left of the overlay
|
|
; (r6,r7): coordinates of bottom-right of the overlay
|
|
|
|
; now we need to check if:
|
|
; - (r4,r5) is greater than or equal to (r0,r1)
|
|
; and
|
|
; - (r6,r7) is less than or equal to (r0,r1)
|
|
|
|
; if carry flag is set, value is less than
|
|
; if carry flag is clear, value is greater than or equal to
|
|
cmp r0, r4
|
|
ifc jmp check_if_overlay_covers_position_fail
|
|
cmp r0, r6
|
|
ifnc jmp check_if_overlay_covers_position_fail
|
|
|
|
cmp r1, r5
|
|
ifc jmp check_if_overlay_covers_position_fail
|
|
cmp r1, r7
|
|
ifnc jmp check_if_overlay_covers_position_fail
|
|
|
|
; if we reached this point then the point is within the bounds of the overlay !!!
|
|
|
|
mov.8 r0, 0
|
|
cmp.8 r0, 0 ; set Z flag
|
|
pop r7
|
|
pop r6
|
|
pop r5
|
|
pop r4
|
|
pop r3
|
|
pop r1
|
|
pop r0
|
|
ret
|
|
check_if_overlay_covers_position_fail:
|
|
mov.8 r0, 1
|
|
cmp.8 r0, 0 ; clear Z flag
|
|
pop r7
|
|
pop r6
|
|
pop r5
|
|
pop r4
|
|
pop r3
|
|
pop r1
|
|
pop r0
|
|
ret
|
|
|
|
; checks if the specified overlay is covering the specified position on screen
|
|
; the overlay must be enabled
|
|
; example:
|
|
; overlay 0 is at (0,0) and is 32x32 in size
|
|
; point (4,2) is covered by overlay 0
|
|
; point (16,16) is covered by overlay 0
|
|
; point (31,31) is covered by overlay 0
|
|
; point (32,32) is NOT covered by overlay 0, because it is outside of the overlay's area
|
|
; this works for overlays of any size, at any position on screen
|
|
; inputs:
|
|
; r0: X coordinate
|
|
; r1: Y coordinate
|
|
; r2: overlay number
|
|
; outputs:
|
|
; Z flag: set if covering, clear if not covering
|
|
check_if_enabled_overlay_covers_position:
|
|
push r3
|
|
push r4
|
|
|
|
mov r3, r2
|
|
or r3, 0x80000300 ; bitwise or the overlay number with the command to get the overlay enable status
|
|
in r4, r3
|
|
|
|
cmp r4, 0
|
|
pop r4
|
|
pop r3
|
|
ifnz jmp check_if_enabled_overlay_covers_position_is_enabled
|
|
cmp r4, 1 ; r4 is known to be zero at this point, so compare it with 1 to clear the Z flag
|
|
ret
|
|
check_if_enabled_overlay_covers_position_is_enabled:
|
|
call check_if_overlay_covers_position
|
|
ret
|
|
|
|
; converts coordinates to be relative to the position of the specified overlay
|
|
; the overlay can be enabled or disabled
|
|
; example:
|
|
; overlay is at (16,16)
|
|
; (20,20) is specified
|
|
; (4,4) will be returned
|
|
; inputs:
|
|
; r0: X coordinate
|
|
; r1: Y coordinate
|
|
; r2: overlay number
|
|
; outputs:
|
|
; r0: relative X coordinate
|
|
; r1: relative Y coordinate
|
|
make_coordinates_relative_to_overlay:
|
|
push r2
|
|
push r3
|
|
|
|
or r2, 0x80000000 ; bitwise or the overlay number with the command to get the overlay position
|
|
in r2, r2
|
|
mov r3, r2
|
|
and r2, 0x0000FFFF ; r2: overlay X position
|
|
sra r3, 16 ; r3: overlay Y position
|
|
|
|
sub r0, r2
|
|
sub r1, r3
|
|
|
|
pop r3
|
|
pop r2
|
|
ret |