forked from TCShenanigans/symphony_stdlib
Remove graphics code from this PR
This commit is contained in:
@@ -1,672 +0,0 @@
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; 32 bit graphics library for Symphony
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include globals
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include errno
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const SCREEN_SETTING_MODE = 0 ; Use zr instead
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const SCREEN_SETTING_DATA_OFFSET = 1
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const SCREEN_SETTING_RESOLUTION = 2
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const SCREEN_SETTING_FOREGROUND_COLOR = 2
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const SCREEN_SETTING_BACKGROUND_COLOR = 3
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const SCREEN_SETTING_FONT = 4
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const SCREEN_MODE_TEXT_8 = 0
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const SCREEN_MODE_TEXT_32 = 1
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const SCREEN_MODE_GRAPHICS_8 = 2
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const SCREEN_MODE_GRAPHICS_32 = 3
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pub set_graphics_mode:
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; u16 set_graphics_mode(void *FB_ptr, size_t FB_size, u8 bit_per_pixel, u16 width, bool clear, bool double_buf)
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; Sets the screen to graphics mode, the resolution, and colour depth.
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; Optionally clears the screen.
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;
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; Arguments:
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; - r1: Point to allocated framebuffer
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; - r2: Size of FB allocation, in bytes
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; - r3: Bits per pixel: One of `8` or `32`
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; - r4: Width - height is set to `width / 4 * 3`
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; - r5: If non-zero, clears the current framebuffer.
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; - r6: If non-zero, enable double buffering
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; Returns:
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; - r1: Status
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; * 0 OK
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; * SCREEN_INVALID_SIZE width invalid
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; * SCREEN_INVALID_MODE bits_per_pixel invalid
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; * SCREEN_FB_TOO_SMALL allocation too small
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; Clobbers:
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; - r2-r6, flags
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; Globals written:
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; - LOG_STRIDE
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; - FB_WIDTH
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; - FB_HEIGHT
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; - BITS_PER_PIXEL
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; Check the magic number
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load_16 flags, [globals.MAGIC_ADDRESS]
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cmp flags, globals.MAGIC_VALUE
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je set_graphics_mode_magic_ok
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mov flags, errno.MAGIC_BAD
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jmp r13 ; return
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set_graphics_mode_magic_ok:
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push r8 ; LOG Bytes/pixel
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push r9 ; Log width
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push r10 ; Height
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push r11 ; Size of FB in bytes/pixels
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cmp r3, 32
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jne not_32_bit_mode
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mov r3, SCREEN_MODE_GRAPHICS_32
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mov r8, 2
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jmp mode_ok
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not_32_bit_mode:
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cmp r3, 8
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jne invalid_mode
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mov r3, SCREEN_MODE_GRAPHICS_8
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mov r8, 0
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jmp mode_ok
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invalid_mode:
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pop r11
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pop r10
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pop r9
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pop r8
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mov flags, errno.SCREEN_INVALID_MODE
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jmp r13 ; return
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mode_ok:
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; Width must be between 4 and 1024
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cmp r4, 1024 ; max width of screen
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ja width_invalid
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cmp r4, 4
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jb width_invalid
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; Is width a power of two?
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mov r9, 10
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mov r10, 1024
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log_width_loop:
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cmp r4, r10
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je width_ok
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lsr r10, r10, 1
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sub r9, r9, 1
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cmp r9, 4
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jae log_width_loop
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width_invalid:
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pop r11
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pop r10
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pop r9
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pop r8
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mov flags, errno.SCREEN_INVALID_WIDTH
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jmp r13 ; return
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width_ok:
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; Now r9 = log width
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; height = width/4 * 3
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lsr r4, r4, 2
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lsl r10, r4, 1
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add r10, r10, r4 ; height
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; Compute size of FB
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lsl r11, r10, r9 ; Size of FB in pixels
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lsl r11, r11, r8 ; Size of FB in bytes
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; If double buffering..
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cmp r6, 0
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je single_buff
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; ..we need twice the space
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lsl r11, r11, 1
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single_buff:
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cmp r2, r11
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jae size_ok
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pop r11
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pop r10
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pop r9
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pop r8
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mov flags, errno.SCREEN_FB_TOO_SMALL
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jmp r13 ; return
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size_ok:
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; Set screen mode
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screen zr, r3
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; Set screen size
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mov flags, SCREEN_SETTING_RESOLUTION
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; Setting is width/4 - 1
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sub r4, r4, 1
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screen flags, r4
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; Restore width
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add r4, r4, 1
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lsl r4, r4, 2
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; Set FB pointer
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; If double buffering..
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cmp r6, 0
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je save_fb_single_buff
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; ..we want the size of each FB
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lsr r11, r11, 1
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store_32 [globals.FB_SIZE_BYTE], r11
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store_32 [globals.FB_DISPLAY_PTR], r2
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mov r3, SCREEN_SETTING_DATA_OFFSET
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screen r3, r2
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add r2, r2, r11
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jmp save_fb_done
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save_fb_single_buff:
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store_32 [globals.FB_SIZE_BYTE], r11
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store_32 [globals.FB_DISPLAY_PTR], r2
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mov r3, SCREEN_SETTING_DATA_OFFSET
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screen r3, r2
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save_fb_done:
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store_32 [globals.FB_DRAW_PTR], r2
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store_16 [globals.FB_WIDTH_PX], r4
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store_16 [globals.FB_HEIGHT_PX], r10
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store_8 [globals.FB_LOG_WIDTH], r9
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store_8 [globals.FB_LOG_BPP], r8
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mov flags, 1
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lsl r8, flags, r8
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store_8 [globals.FB_BYTES_PER_PIXEL], r8
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mov r1, r2 ; Return draw FB
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mov r3, 0
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mov r4, 0
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; TODO call clear
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nor r2, zr, 0xff ; Colour = White (32-bit)
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pop r11
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pop r10
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pop r9
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pop r8
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mov flags, 0 ; OK
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jmp r13 ; return
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pub set_text_mode:
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; u16 set_text_mode(void *FB_ptr, size_t FB_size, u8 bit_per_pixel, u8 font, bool clear, bool double_buf)
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; Sets the screen to text mode, the font, and colour depth. Also sets fore ground and background colors.
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; Optionally clears the screen.
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; Arguments:
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; - r1: Address of allocated framebuffer
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; - r2: Size of FB allocation, in bytes
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; - r3: Bits per pixel: One of `8` or `32`
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; - r4: Font, one of {0,1,2,3}
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; - r5: If non-zero, clears the current framebuffer.
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; - r6: If non-zero, enable double buffering
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; Returns:
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; - r1: Status
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; * 0 OK
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; * SCREEN_INVALID_SIZE width invalid
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; * SCREEN_INVALID_MODE bits_per_pixel invalid
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; * SCREEN_FB_TOO_SMALL allocation too small
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; Clobbers:
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; - r2-r6, flags
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; Globals written:
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; - LOG_STRIDE
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; - FB_WIDTH
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; - FB_HEIGHT
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; - BITS_PER_PIXEL
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; Check the magic number
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load_16 flags, [globals.MAGIC_ADDRESS]
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cmp flags, globals.MAGIC_VALUE
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je set_text_mode_magic_ok
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mov flags, errno.MAGIC_BAD
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jmp r13 ; return
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set_text_mode_magic_ok:
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;TODO: Sanity checks
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;TODO: ?Clear screen
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push r8 ; LOG Bytes/pixel
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push r9 ; Log width
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push r10 ; Height
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push r11 ; Size of FB in bytes/pixels
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cmp r3, 32
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jne not_32_bit_text_mode
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mov r3, SCREEN_MODE_TEXT_32
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mov r8, 2
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jmp text_mode_ok
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not_32_bit_text_mode:
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cmp r3, 8
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jne invalid_text_mode
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mov r3, SCREEN_MODE_TEXT_8
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mov r8, 0
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jmp text_mode_ok
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invalid_text_mode:
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pop r11
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pop r10
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pop r9
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pop r8
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mov flags, errno.SCREEN_INVALID_MODE
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jmp r13 ; return
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text_mode_ok:
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; Set screen mode
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screen zr, r3
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; Set FB pointer
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; If double buffering..
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cmp r6, 0
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je save_fb_single_text_buff
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; ..we want the size of each FB
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lsr r11, r11, 1
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store_32 [globals.FB_SIZE_BYTE], r11
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store_32 [globals.FB_DISPLAY_PTR], r2
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mov r3, SCREEN_SETTING_DATA_OFFSET
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screen r3, r2
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add r2, r2, r11
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jmp save_fb_text_done
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save_fb_single_text_buff:
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store_32 [globals.FB_SIZE_BYTE], r11
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store_32 [globals.FB_DISPLAY_PTR], r2
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mov r3, SCREEN_SETTING_DATA_OFFSET
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screen r3, r2
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save_fb_text_done:
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store_32 [globals.FB_DRAW_PTR], r2
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; Set screen font
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; Only 0, 1, 2, 3 are valid
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and r4, r4, 3
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mov flags, SCREEN_SETTING_FONT
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screen flags, r4
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; Set foreground to white
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mov flags, SCREEN_SETTING_FOREGROUND_COLOR
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nor r4, zr, 0xff ; White
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screen flags, r4
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; Set background to black
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mov flags, SCREEN_SETTING_BACKGROUND_COLOR
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screen flags, zr
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pop r11
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pop r10
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pop r9
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pop r8
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mov flags, 0 ; OK
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jmp r13 ; return
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pub set_text_mode_default:
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; u16 set_text_mode_default(void *FB_ptr)
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; Sets the screen to default text mode, the font, and colour depth. Also sets fore ground and background colors.
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; Does not clear the screen.
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; Size of allcation is not checked
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;
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; Arguments:
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; - r1: Address of allocated framebuffer
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; Returns:
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; - flags: 0 ; ok, never fails
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; Clobbers:
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; - r1, flags
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; Globals written:
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; - FB_DISPLAY_PTR
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; - FB_DRAW_PTR
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; - FRAME_BUFFER_SIZE
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; Set screen mode to default 8 bit text
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screen zr, zr
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; Set FB pointer
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store_32 [globals.FB_DISPLAY_PTR], r1
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store_32 [globals.FB_DRAW_PTR], r1
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; Size is 96*40*1 byte
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mov r1, 3840
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store_32 [globals.FB_SIZE_BYTE], r1
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mov flags, SCREEN_SETTING_DATA_OFFSET
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screen flags, r1
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; Set default screen font
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mov flags, SCREEN_SETTING_FONT
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screen flags, zr
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; Set foreground to white
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mov flags, SCREEN_SETTING_FOREGROUND_COLOR
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nor r1, zr, 0xff ; White
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screen flags, r1
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; Set background to black
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mov flags, SCREEN_SETTING_BACKGROUND_COLOR
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screen flags, zr
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mov flags, 0 ; OK
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jmp r13
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pub clear:
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; void clear()
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; Paints the whole screen black
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;
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; Arguments:
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; - None
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; Clobbers:
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; - r1: Color
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; - r2: fill_screen
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; - r3: fill_screen
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; - r4: fill_screen
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; - flags
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mov r1, 0 ; Black
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; Fall through
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pub fill_screen:
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; void fill_screen(u32 color)
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; Fills the whole screen in a single color.
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;
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; Arguments:
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; - r1: Color, 32 bit RGB0
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; Clobbers:
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; - r2: Pixel pointer
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; - r3: End address
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; - r4: Stride
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; - flags
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; Reads globals:
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; - FB_DRAW_PTR
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; - LOG_BPP
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; - LOG_WIDTH
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; - PIXEL_HEIGHT
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load_8 r2, [globals.FB_LOG_WIDTH]
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load_16 r3, [globals.FB_HEIGHT_PX]
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lsl r3, r3, r2
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load_8 r4, [globals.FB_LOG_BPP]
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lsl r3, r3, r4 ; Num bytes in FB
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load_32 r2, [globals.FB_DRAW_PTR]
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add r3, r3, r2 ; End of FB
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load_8 r4, [globals.FB_BYTES_PER_PIXEL]
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fill_screen_loop:
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; Screen is always a multiple of 4*3
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; we can unroll this 12 times.
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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store_32 [r2], r1
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add r2, r2, r4
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cmp r2, r3
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jb fill_screen_loop
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jmp r13 ; return
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pub switch_buffers: ; SHOULD BE INLINED
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; void switch_buffers()
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; Swaps the display and draw buffers, and updates the screen to use the new display buffer.
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;; Safe to run when single buffered.
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;
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||||
; Arguments:
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||||
; - None
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||||
; Returns:
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||||
; - None
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||||
; Clobbers:
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||||
; - r1: Old display FB => new draw FB
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; - r2: Old draw FB => new display FB
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; - flags
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; Globals written:
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; - FB_DISPLAY_PTR
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; - FB_DRAW_PTR
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load_32 r1, [globals.FB_DISPLAY_PTR]
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load_32 r2, [globals.FB_DRAW_PTR]
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mov flags, SCREEN_SETTING_DATA_OFFSET
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screen flags, r2
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||||
store_32 [globals.FB_DISPLAY_PTR], r2
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||||
store_32 [globals.FB_DRAW_PTR], r1
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||||
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||||
jmp r13 ; return
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||||
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||||
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||||
pub draw_pixel:
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; void draw_pixel(u32 color, u16 x, u16 y)
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; Draw pixel at the position, no checks on position, can potentally write to any memory.
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; Framebuffer pointer is stored in FB_PTR.
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||||
;
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||||
; Arguments:
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; - r1 Color 24 bit RGB0 PRESERVED
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||||
; - r2 X coord PRESERVED
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||||
; - r3 Y coord PRESERVED
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; - r4-r7 ignored but PRESERVED
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; Result:
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; - None
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||||
; Clobbers:
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||||
; - flags
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||||
; Globals read:
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||||
; - FB_DRAW_PTR
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||||
; - LOG_WIDTH
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||||
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; Screen is `1 << WIDTH pixels wide
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||||
load_8 flags, [globals.FB_LOG_WIDTH]
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||||
; Compute pixel address
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||||
lsl flags, r4, flags ; Y * width
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||||
add flags, flags, r3 ; Y * width + X
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||||
lsl flags, flags, 2 ; pixel to address
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||||
load_32 r1, [globals.FB_DRAW_PTR]
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||||
add flags, flags, r1 ; += frambuffer_ptr
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||||
; Set pixel value
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||||
store_32 [flags], r2
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||||
jmp r13 ; return
|
||||
|
||||
|
||||
pub draw_line_h:
|
||||
; void draw_line_h(u32 color, u16 x0, u16 y, u16 x1)
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||||
; Draws a straight horizontal line from (x0, y) to (x1, y) (inclusive) using `color`
|
||||
; on to the current `FB_DRAW_PTR` buffer.
|
||||
;
|
||||
; Arguments:
|
||||
; - r1: Color 24 bit RGB0 PRESERVED
|
||||
; - r2: X0 coord
|
||||
; - r3: Y coord PRESERVED
|
||||
; - r4: X1 coord
|
||||
; Returns:
|
||||
; - r1: Color 24 bit RGB0 PRESERVED
|
||||
; - r2: X1 coord
|
||||
; - r3: Y coord PRESERVED
|
||||
; Clobbers:
|
||||
; - r7, flags
|
||||
|
||||
push r13
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||||
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||||
; if x0 > x1
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||||
; dx = -1
|
||||
; else
|
||||
; dx = +1
|
||||
; endif
|
||||
cmp r4, r2
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||||
or r7, flags, 0x02
|
||||
lsl r7, r7, 29
|
||||
asr r7, r7, 30
|
||||
|
||||
jmp draw_line_h_loop_in
|
||||
draw_line_h_loop:
|
||||
add r2, r2, r7
|
||||
draw_line_h_loop_in:
|
||||
qcall draw_pixel
|
||||
cmp r2, r4
|
||||
jne draw_line_h_loop
|
||||
|
||||
pop r13
|
||||
jmp r13 ; return
|
||||
|
||||
|
||||
pub draw_line_v:
|
||||
; void draw_line_v(u32 color, u16 x, u16 _, u16 y0, u16 x1)
|
||||
; Draws a straight verticle line from (x, y0) to (x, y1) (inclusive) using `color`
|
||||
; on to the current `FB_DRAW_PTR` buffer.
|
||||
;
|
||||
; Arguments:
|
||||
; - r1: Color 24 bit RGB0 PRESERVED
|
||||
; - r2: X coord PRESERVED
|
||||
; - r3: Y0 coord
|
||||
; - r4: ignored but PRESERVED
|
||||
; - r5: Y1 coord
|
||||
|
||||
; Returns:
|
||||
; - r1: Color 24 bit RGB0 PRESERVED
|
||||
; - r2: X coord PRESERVED
|
||||
; - r3: Y1 coord
|
||||
; Clobbers:
|
||||
; - r7, flags
|
||||
|
||||
push r13
|
||||
|
||||
; if y0 > y1
|
||||
; dy = -1
|
||||
; else
|
||||
; dy = +1
|
||||
; endif
|
||||
cmp r5, r3
|
||||
or r7, flags, 0x02
|
||||
lsl r7, r7, 29
|
||||
asr r7, r7, 30
|
||||
|
||||
jmp draw_line_v_loop_in
|
||||
draw_line_v_loop:
|
||||
add r3, r3, r7
|
||||
draw_line_v_loop_in:
|
||||
qcall draw_pixel
|
||||
cmp r3, r5
|
||||
jne draw_line_v_loop
|
||||
|
||||
pop r13
|
||||
jmp r13 ; return
|
||||
|
||||
|
||||
pub draw_line:
|
||||
; void draw_line(u32 color, u16 x0, u16 y0, u16 x1, u16 y1)
|
||||
; Draws a straight line from (x0, y0) to (x1, y1) (inclusive) using `color`
|
||||
; on to the current `FB_DRAW_PTR` buffer.
|
||||
;
|
||||
; Arguments:
|
||||
; - r1: Color 24 bit RGB0 PRESERVED
|
||||
; - r2: X0 coord
|
||||
; - r3: Y0 coord
|
||||
; - r4: X1 coord
|
||||
; - r5: Y1 coord
|
||||
; Returns:
|
||||
; - r1: Color 24 bit RGB0 PRESERVED
|
||||
; - r2: X1 coord
|
||||
; - r3: Y1 coord
|
||||
; Clobbers:
|
||||
; - r4-r7, flags
|
||||
; Globals read:
|
||||
; - FB_DRAW_PTR
|
||||
; - FB_DRAW_STRIDE
|
||||
; - ...others I expect
|
||||
|
||||
; push r11 ; sy
|
||||
; push r10 ; dy
|
||||
; push r9 ; sx
|
||||
; push r8 ; dx
|
||||
|
||||
; int dx = abs(x1-x0), sx = x0<x1 ? 1 : -1;
|
||||
cmp r2, r4
|
||||
ja draw_line_move_left
|
||||
jb draw_line_move_right
|
||||
; if x0 == x1
|
||||
jmp draw_line_v ; tail call
|
||||
; elif x0 < x1
|
||||
draw_line_move_right:
|
||||
push r8 ; dx
|
||||
push r9 ; sx
|
||||
sub r8, r4, r2
|
||||
mov r9, 1
|
||||
jmp draw_line_move_right_done
|
||||
; else x0 > x1
|
||||
draw_line_move_left:
|
||||
push r8 ; dx
|
||||
push r9 ; sx
|
||||
sub r8, r2, r4
|
||||
nor r9, zr, zr ; sx = -1
|
||||
; endif
|
||||
draw_line_move_right_done:
|
||||
|
||||
; int dy = -abs(y1-y0), sy = y0<y1 ? 1 : -1;
|
||||
cmp r3, r5
|
||||
jb draw_line_move_down
|
||||
ja draw_line_move_up
|
||||
; if y0 == y0
|
||||
; Restore r8, r9
|
||||
pop r9
|
||||
pop r8
|
||||
jmp draw_line_h ; tail call
|
||||
; elif y0 < y1
|
||||
draw_line_move_down:
|
||||
push r10 ; dy
|
||||
push r11 ; sy
|
||||
sub r10, r3, r5
|
||||
mov r11, 1
|
||||
jmp draw_line_move_down_done
|
||||
; else y0 > y1
|
||||
draw_line_move_up:
|
||||
push r10 ; dy
|
||||
push r11 ; sy
|
||||
sub r10, r5, r3
|
||||
nor r11, zr, zr ; sy = -1
|
||||
; endif
|
||||
draw_line_move_down_done:
|
||||
|
||||
push r12 ; err, err2
|
||||
push r13 ; lr
|
||||
|
||||
; int err = dx+dy /* error value e_xy */
|
||||
add r12, r8, r10
|
||||
; loop while(true)
|
||||
draw_line_loop:
|
||||
|
||||
qcall draw_pixel
|
||||
; err2 = 2*err;
|
||||
lsl r12, r12, 1
|
||||
; if (err2 >= dy) { /* e_xy+e_x > 0 */
|
||||
cmp r12, r10
|
||||
lsr r12, r12, 1 ; restore err
|
||||
jl draw_line_loop_skip_x
|
||||
; if (x0 == x1) break;
|
||||
cmp r2, r4
|
||||
je draw_line_loop_done
|
||||
; err += dy
|
||||
add r12, r12, r10
|
||||
; x0 += sx;
|
||||
add r2, r2, r9
|
||||
draw_line_loop_skip_x:
|
||||
|
||||
; err2 = 2*err;
|
||||
lsl r12, r12, 1
|
||||
; if (err2 <= dx) { /* e_xy+e_y < 0 */
|
||||
cmp r12, r8
|
||||
lsl r12, r12, 1 ; restore err
|
||||
jl draw_line_loop_skip_y
|
||||
; if (y0 == y1) break;
|
||||
cmp r3, r5
|
||||
je draw_line_loop_done
|
||||
; err += dx
|
||||
add r12, r12, r8
|
||||
; y0 += sy
|
||||
add r3, r3, r11
|
||||
draw_line_loop_skip_y:
|
||||
jmp draw_line_loop
|
||||
; endloop
|
||||
draw_line_loop_done:
|
||||
|
||||
pop r13
|
||||
pop r12
|
||||
pop r11
|
||||
pop r10
|
||||
pop r9
|
||||
pop r8
|
||||
jmp r13 ; return
|
||||
Reference in New Issue
Block a user