gouraund tris, the gp commands are a thing of beauty

code/graphics_system/dsl.s

@@ -41,4 +41,4 @@ rarg_3 equ $a3
 rret_0 equ $v0
 rret_1 equ $v1
 ; Subroutine return address when doing a sub
-rret_addr equ $ra
+rret_addr equ $ra

code/graphics_system/gp.s

@@ -0,0 +1,129 @@
+; IO PORT
+IO_BASE_ADDR equ 0x1F80 ; IO Ports Memory map base address
+
+; GPU Registers
+gpio_port0 equ 0x1810 ; 1F801810h-Write GP0: Send GP0 Commands/Packets (Rendering and VRAM Access)
+gpio_port1 equ 0x1814 ; 1F801814h-Write GP1: Send GP1 Commands (Display Control) (and DMA Control)
+
+; GPU Command Format: [7:8] Command (8-bit), [0:6] Paraemter (24-bit)
+
+gcmd_offset equ 24
+
+gp_Reset equ 0x0 << gcmd_offset
+
+; On:  0x0
+; Off: 0x1
+gp_DisplayEnabled  equ (0x03 << gcmd_offset)  | 0x0
+gp_DisplayDisabled equ (0x03 << gcmd_offset)  | 0x1
+
+; GP1(08h) - Display mode
+; 0-1   Horizontal Resolution 1     (0=256, 1=320, 2=512, 3=640) ;GPUSTAT.17-18
+; 2     Vertical Resolution         (0=240, 1=480, when Bit5=1)  ;GPUSTAT.19
+; 3     Video Mode                  (0=NTSC/60Hz, 1=PAL/50Hz)    ;GPUSTAT.20
+; 4     Display Area Color Depth    (0=15bit, 1=24bit)           ;GPUSTAT.21
+; 5     Vertical Interlace          (0=Off, 1=On)                ;GPUSTAT.22
+; 6     Horizontal Resolution 2     (0=256/320/512/640, 1=368)   ;GPUSTAT.16
+; 7     Flip screen horizontally    (0=Off, 1=On, v1 only)       ;GPUSTAT.14
+; 8-23  Not used (zero)
+@DisplayMode equ 0x08
+gp_DisplayMode_320x240_15bit_NTSC equ @DisplayMode << gcmd_offset | 0x0 << 7 | 0x0 << 6 | 0x0 << 5 | 0x0 << 4 | 0x0 << 3 | 0x0 << 2 | 0x1
+
+; GP1(06h) - Horizontal Display range (on Screen)
+; X2 = X1 + pixels * cycles_per_pix
+; 0  - 11 X1 (260h + 0)       ; 12bit ; \ counted in video clock units,
+; 12 - 23 X2 (260h + 320 * 8) ; 12bit ; / relative to HSYNC
+gp_HorizontalDisplayRange_3168_608 equ 0x06 << gcmd_offset | 0xC60 << 12 | 0x260
+
+; GP1(07h) - Vertical Display range (on Screen)
+; 0  - 9  Y1 (NTSC = 88h - (240 / 2), (PAL = A3h - (288 / 2))  ; \ scanline numbers on screen,
+; 10 - 19 Y2 (NTSC = 88h + (240 / 2), (PAL = A3h + (288 / 2))  ; / relative to VSYNC
+; 20 - 23 Not used (zero)
+gp_VerticalDisplayRange_264_24 equ 0x07 << gcmd_offset | 264 << 10 | 24
+
+;GP0(E1h) - Draw Mode setting (aka "Texpage")
+; 0 - 3   Texture page X Base       (N * 64)  (ie. in 64-halfword steps)                       ; GPUSTAT.0-3
+; 4       Texture page Y Base 1     (N * 256) (ie. 0, 256, 512 or 768)                         ; GPUSTAT.4
+; 5 - 6   Semi-transparency         (0 = B / 2 + F / 2, 1 = B + F, 2 = B - F, 3 = B + F / 4)   ; GPUSTAT.5-6
+; 7 - 8   Texture page colors       (0 = 4 bit, 1 = 8bit, 2 = 15bit, 3 = Reserved)             ; GPUSTAT.7-8
+; 9       Dither 24bit to 15bit     (0=Off / strip LSBs, 1 = Dither Enabled)                   ; GPUSTAT.9
+; 10      Drawing to display area   (0=Prohibited, 1=Allowed)                                  ; GPUSTAT.10
+; 11      Texture page Y Base 2     (N * 512) (only for 2 MB VRAM)                             ; GPUSTAT.15
+; 12      Textured Rectangle X-Flip (BIOS does set this bit on power-up...?)
+; 13      Textured Rectangle Y-Flip (BIOS does set it equal to GPUSTAT.13...?)
+; 14 - 23 Not used (should be 0)
+; 24 - 31 Command  (E1h)
+gp_ModeSetting_DrawAllowed equ 10
+gp_ModeSetting_DipArea     equ 0xE1 << gcmd_offset | 0x1 << gp_ModeSetting_DrawAllowed
+
+; GP0(E3h) - Set Drawing Area top left (X1,Y1)
+; GP0(E4h) - Set Drawing Area bottom right (X2,Y2)
+; Sets the drawing area corners. The Render commands GP0(20h..7Fh) are automatically clipping any pixels that are outside of this region.
+; 0  - 9   X-coordinate (0..1023)
+; 10 - 18  Y-coordinate (0..511)   ; \ on v0 GPU (max 1 MB VRAM)
+; 19 - 23  Not used (zero)         ; /
+; 10 - 19  Y-coordinate (0..1023)  ; \ on v2 GPU (max 2 MB VRAM)
+; 20 - 23  Not used (zero)         ; /
+; 24 - 31  Command  (Exh)
+gp_SetArea_TopLeft     equ 0xE3 << gcmd_offset
+gp_SetArea_BottomRight equ 0xE4 << gcmd_offset
+
+; GP0(E5h) - Set Drawing Offset (X,Y)
+; 0-9    X-coordinate (0..1023)
+; 10-18  Y-coordinate (0..511)   ;\on v0 GPU (max 1 MB VRAM)
+; 19-23  Not used (zero)         ;/
+; 10-19  Y-coordinate (0..1023)  ;\on v2 GPU (max 2 MB VRAM)
+; 20-23  Not used (zero)         ;/
+; 24-31  Command  (Exh)
+gp_SetOffset equ 0xE5 << gcmd_offset
+
+; GPU Memory Transfer Commands
+
+; GP0(02h) Fill Vram
+; GP0(02h) - Fill Rectangle in VRAM
+; 1st  Color+Command     (CcBbGgRrh)  ;24bit RGB value (see note)
+; 2nd  Top Left Corner   (YyyyXxxxh)  ;Xpos counted in halfwords, steps of 10h
+; 3rd  Width+Height      (YsizXsizh)  ;Xsiz counted in halfwords, steps of 10h
+ ; Fills the area in the frame buffer with the value in RGB. 
+ ; Horizontally the filling is done in 16-pixel (32-bytes) units (see below masking/rounding).
+ ; The "Color" parameter is a 24bit RGB value, however, the actual fill data is 16bit: 
+ ; The hardware automatically converts the 24bit RGB value to 15bit RGB (with bit15=0).
+ ; Fill is NOT affected by the Mask settings (acts as if Mask.Bit0,1 are both zero).
+gp_RectFillVM  equ 0x02 << gcmd_offset
+
+; GPU Render Polygon Commands
+
+; When the upper 3 bits of the first GP0 command are set to 1 (001), 
+; then the command can be decoded using the following bitfield:
+; bit number   value   meaning
+; 31-29        001     polygon render
+; 28           1/0     gouraud / flat shading
+; 27           1/0     4 / 3 vertices
+; 26           1/0     textured / untextured
+; 25           1/0     semi-transparent / opaque
+; 24           1/0     raw texture / modulation
+; 23-0         rgb     first color value.
+gp_Poly_FirstColor   equ          0
+gp_Poly_RawTexture   equ 1    << 24
+gp_Poly_SemiTrans    equ 1    << 25
+gp_Poly_Textured     equ 1    << 26
+gp_Poly_Quad         equ 1    << 27
+gp_Poly_Tri          equ 0    << 27
+gp_Poly_ShadeFlat    equ 0    << 28
+gp_Poly_ShadeGourand equ 1    << 28
+gp_Polygon           equ 1    << 29
+
+gp_Quad equ gp_Polygon | gp_Poly_Quad
+
+gp_b10_X equ 0
+gp_b10_Y equ 10
+gp_b16_X equ 0
+gp_b16_Y equ 16
+
+.macro gp_push_pak, port, reg_scratch, packet
+	load_imm   reg_scratch, packet
+	store_word reg_scratch, port 
+.endmacro
+.macro gcmd_push, port, reg_scratch, cmd
+	load_imm   reg_scratch, cmd
+	store_word reg_scratch, port 
+.endmacro

code/graphics_system/hello_gouraud.s

@@ -0,0 +1,70 @@
+.psx
+.create "./build/hello_gouraud.bin", 0x80010000
+
+.include "./code/graphics_system/dsl.s"
+.include "./code/graphics_system/gp.s"
+
+; Entry Point of Code
+.org 0x80010000
+
+Color_RedFF           equ 0x0000FF
+Color_22              equ 0x222222
+Color_PS_CadmiumRed   equ 0x2400DF
+Color_PS_CelticBlue   equ 0x723F00
+Color_PS_GoldenPoppy  equ 0x00C3F3
+Color_PS_PersianGreen equ 0x9FAC00
+
+Display_Width      equ 320
+Display_Height     equ 239
+Display_HalfWidth  equ 320 / 2
+Display_HalfHeight equ 240 / 2
+
+main:
+	reg_io_offset equ rtmp_0
+	load_uimm rtmp_0, IO_BASE_ADDR
+
+	gp0 equ gpio_port0(reg_io_offset)
+	gp1 equ gpio_port1(reg_io_offset)
+
+; Setup Display Control
+	gcmd_push gp0, rtmp_1, gp_Reset
+	gcmd_push gp0, rtmp_1, gp_DisplayEnabled
+	gcmd_push gp0, rtmp_1, gp_DisplayMode_320x240_15bit_NTSC
+	gcmd_push gp0, rtmp_1, gp_HorizontalDisplayRange_3168_608
+	gcmd_push gp0, rtmp_1, gp_VerticalDisplayRange_264_24
+	gcmd_push gp0, rtmp_1, gp_ModeSetting_DipArea
+	gcmd_push gp0, rtmp_1, 		gp_SetArea_TopLeft     | 0              << gp_b10_Y | 0             << gp_b10_X
+	gcmd_push gp0, rtmp_1, 		gp_SetArea_BottomRight | Display_Height << gp_b10_Y | Display_Width << gp_b10_X
+	gcmd_push gp0, rtmp_1, 		gp_SetOffset           | 0              << gp_b10_Y | 0             << gp_b10_X
+	gcmd_push gp0, rtmp_1, gp_RectFillVM | Color_22
+	gcmd_push gp0, rtmp_1, 		0              << gp_b16_Y | 0             << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		Display_Height << gp_b16_Y | Display_Width << gp_b16_X
+; Draw a flat-shaded quad
+	gcmd_push gp0, rtmp_1, gp_Quad | Color_PS_CelticBlue
+	gcmd_push gp0, rtmp_1, 		 15 * -1 + Display_HalfHeight << gp_b16_Y |    0 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		 24 * -1 + Display_HalfHeight << gp_b16_Y |  100 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		-30 * -1 + Display_HalfHeight << gp_b16_Y | -100 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		-50 * -1 + Display_HalfHeight << gp_b16_Y |   55 + Display_HalfWidth << gp_b16_X
+; Draw a flat-shaded triangle
+	gcmd_push gp0, rtmp_1, gp_Polygon | Color_PS_GoldenPoppy
+	gcmd_push gp0, rtmp_1, 		100 * -1 + Display_HalfHeight << gp_b16_Y | -100 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		 20 * -1 + Display_HalfHeight << gp_b16_Y |   20 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		 50 * -1 + Display_HalfHeight << gp_b16_Y |   30 + Display_HalfWidth << gp_b16_X
+	; Bonus traingle
+	gcmd_push gp0, rtmp_1, gp_Polygon | Color_PS_CadmiumRed
+	gcmd_push gp0, rtmp_1, 		  50 * -1 + Display_HalfHeight << gp_b16_Y | -100 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		   0 * -1 + Display_HalfHeight << gp_b16_Y |   20 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 		-100 * -1 + Display_HalfHeight << gp_b16_Y |   30 + Display_HalfWidth << gp_b16_X
+	; Gourand shaded triangle
+	gcmd_push gp0, rtmp_1, gp_Polygon | gp_Poly_ShadeGourand | Color_PS_PersianGreen
+	gcmd_push gp0, rtmp_1, 		-35 * -1 + Display_HalfHeight << gp_b16_Y |  145 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 0x00 << 16 | Color_PS_GoldenPoppy
+	gcmd_push gp0, rtmp_1, 		  0 * -1 + Display_HalfHeight << gp_b16_Y |   50 + Display_HalfWidth << gp_b16_X
+	gcmd_push gp0, rtmp_1, 0x00 << 16 | Color_PS_CadmiumRed
+	gcmd_push gp0, rtmp_1, 		 40 * -1 + Display_HalfHeight << gp_b16_Y |   60 + Display_HalfWidth << gp_b16_X
+
+idle:
+	jump idle :: nop
+
+.close
+

code/graphics_system/hellogpu.s

@@ -118,7 +118,9 @@ gp_Poly_Quad         equ 1    << 27
 gp_Poly_Tri          equ 0    << 27
 gp_Poly_ShadeFlat    equ 0    << 28
 gp_Poly_ShadeGourand equ 1    << 28
-gp_Polygon           equ 0x20 << gcmd_offset
+gp_Polygon           equ 1    << 29
+
+gp_Quad equ gp_Polygon | gp_Poly_Quad
 
 gp_b10_X equ 0
 gp_b10_Y equ 10
@@ -135,6 +137,7 @@ gp_b16_Y equ 16
 .endmacro
 
 Color_RedFF          equ 0x0000FF
+Color_22             equ 0x222222
 Color_PS_CadmiumRed  equ 0x2400DF
 Color_PS_GoldenPoppy equ 0x00C3F3
 Color_PS_CelticBlue  equ 0x723F00
@@ -179,12 +182,23 @@ main:
 	store_word rtmp_1, gpio_port0(reg_io_offset)
 ; Clear the screen
 ; 1. GP0: Fill rectangle on display area
-	load_imm   rtmp_1, gp_RectFillVM | Color_PS_CelticBlue
+	load_imm   rtmp_1, gp_RectFillVM | Color_22
 	store_word rtmp_1, gpio_port0(reg_io_offset)
 	load_imm   rtmp_1, 0 << gp_b16_Y | 0 << gp_b16_X
 	store_word rtmp_1, gpio_port0(reg_io_offset)
 	load_imm   rtmp_1, Display_Height << gp_b16_Y | Display_Width << gp_b16_X
 	store_word rtmp_1, gpio_port0(reg_io_offset)
+; Draw a flat-shaded quad
+	load_imm   rtmp_1, gp_Quad | Color_PS_CelticBlue
+	store_word rtmp_1, gpio_port0(reg_io_offset)
+	load_imm   rtmp_1, -1 *  15 + Display_HalfHeight << gp_b16_Y |    0 + Display_HalfWidth << gp_b16_X
+	store_word rtmp_1, gpio_port0(reg_io_offset)
+	load_imm   rtmp_1, -1 *  24 + Display_HalfHeight << gp_b16_Y |  100 + Display_HalfWidth << gp_b16_X
+	store_word rtmp_1, gpio_port0(reg_io_offset)
+	load_imm   rtmp_1, -1 * -30 + Display_HalfHeight << gp_b16_Y | -100 + Display_HalfWidth << gp_b16_X
+	store_word rtmp_1, gpio_port0(reg_io_offset)
+	load_imm   rtmp_1, -1 * -50 + Display_HalfHeight << gp_b16_Y |   55 + Display_HalfWidth << gp_b16_X
+	store_word rtmp_1, gpio_port0(reg_io_offset)
 ; Draw a flat-shaded triangle
 ; 1. GP0: Send packets to GP0 to draw a triangle
 	load_imm   rtmp_1, gp_Polygon | Color_PS_GoldenPoppy

scripts/build.ps1

@@ -37,4 +37,5 @@ function build-program { param(
 # build-program 'warmup' 'exercise_2'
 # build-program 'warmup' 'exercise_3'
 # build-program 'factorial' 'factorial' 
-build-program 'graphics_system' 'hellogpu'
+# build-program 'graphics_system' 'hellogpu'
+build-program 'graphics_system' 'hello_gouraud'