examples: add triangle_rotating example
This commit is contained in:
parent
73428f90b1
commit
8a56e6de94
13
Makefile
13
Makefile
@ -10,17 +10,10 @@ arm9/%.bin: phony
|
||||
arm7/%.bin: phony
|
||||
make -C arm7/ $(notdir $@)
|
||||
|
||||
OBJ = \
|
||||
header.o \
|
||||
arm9/arm9.bin.o \
|
||||
arm7/arm7.bin.o
|
||||
cartridge.elf: $(OBJ)
|
||||
DEFAULT = header.o arm7/arm7.bin.o
|
||||
|
||||
TRIANGLE_OBJ = \
|
||||
header.o \
|
||||
arm9/triangle.bin.o \
|
||||
arm7/arm7.bin.o
|
||||
triangle.elf: $(TRIANGLE_OBJ)
|
||||
triangle.elf: $(DEFAULT) arm9/triangle.bin.o
|
||||
triangle_rotating.elf: $(DEFAULT) arm9/triangle_rotating.bin.o
|
||||
|
||||
TARGET = arm-none-eabi-
|
||||
AARCH = -march=armv4t -mlittle-endian
|
||||
|
||||
@ -16,10 +16,11 @@ OBJ = \
|
||||
|
||||
arm9.elf: $(OBJ)
|
||||
|
||||
foo = start.o examples/triangle.o
|
||||
triangle.elf: $(foo)
|
||||
triangle.elf: start.o examples/triangle.o
|
||||
|
||||
CFLAGS += -I../include
|
||||
triangle_rotating.elf: start.o examples/triangle_rotating.o ../math/cos_table_fp12.o ../math/cos.o
|
||||
|
||||
CFLAGS += -I../include -I../math
|
||||
|
||||
include arm9.mk
|
||||
include ../common.mk
|
||||
|
||||
175
arm9/examples/triangle_rotating.c
Normal file
175
arm9/examples/triangle_rotating.c
Normal file
@ -0,0 +1,175 @@
|
||||
#include "io_registers.h"
|
||||
#include "bits.h"
|
||||
|
||||
#include "math.h"
|
||||
|
||||
void main()
|
||||
{
|
||||
// power control
|
||||
io_registers.a.POWCNT = 0
|
||||
| POWCNT__lcd_output_destination__a_to_upper__b_to_lower
|
||||
| POWCNT__geometry_engine__enable
|
||||
| POWCNT__rendering_engine__enable
|
||||
| POWCNT__lcd__enable;
|
||||
|
||||
// enable bg0 and 3d graphics
|
||||
io_registers.a.DISPCNT = 0
|
||||
| DISPCNT__display_mode__graphics_display
|
||||
| DISPCNT__bg0__enable
|
||||
| DISPCNT__display_selection_for_bg0__3d_graphics
|
||||
;
|
||||
|
||||
// clear matrix stack status
|
||||
io_registers.a.GXSTAT |= GXSTAT__matrix_stack_status__overflow_or_underflow;
|
||||
|
||||
// load identity matrices
|
||||
io_registers.a.MTX_MODE = MTX_MODE__matrix_mode__projection;
|
||||
io_registers.a.MTX_IDENTITY = 0;
|
||||
|
||||
io_registers.a.MTX_MODE = MTX_MODE__matrix_mode__position;
|
||||
io_registers.a.MTX_IDENTITY = 0;
|
||||
|
||||
io_registers.a.MTX_MODE = MTX_MODE__matrix_mode__position_and_vector;
|
||||
io_registers.a.MTX_IDENTITY = 0;
|
||||
|
||||
// disable all 3d effects
|
||||
io_registers.a.DISP3DCNT = 0
|
||||
| DISP3DCNT__clear_image__disable
|
||||
| DISP3DCNT__fog_master__disable
|
||||
| DISP3DCNT__edge_marking__disable
|
||||
| DISP3DCNT__anti_aliasing__disable
|
||||
| DISP3DCNT__alpha_blending__disable
|
||||
| DISP3DCNT__alpha_test__disable
|
||||
| DISP3DCNT__texture_mapping__disable;
|
||||
|
||||
// set the 3d clear color to a dark red
|
||||
io_registers.a.CLEAR_COLOR = 0
|
||||
| CLEAR_COLOR__clear_polygon_id(31)
|
||||
| CLEAR_COLOR__alpha_value(31)
|
||||
| CLEAR_COLOR__blue(1)
|
||||
| CLEAR_COLOR__green(1)
|
||||
| CLEAR_COLOR__red(10);
|
||||
|
||||
// set the depth buffer clear value to the maximum value
|
||||
io_registers.a.CLEAR_DEPTH = CLEAR_DEPTH__value(0x7fff);
|
||||
|
||||
// the following polygons are fully opaque and are not
|
||||
// backface-culled
|
||||
io_registers.a.POLYGON_ATTR = 0
|
||||
| POLYGON_ATTR__alpha_value(31)
|
||||
| POLYGON_ATTR__render_front_surface__enable
|
||||
| POLYGON_ATTR__render_back_surface__enable;
|
||||
|
||||
// the 3d viewport is the entire display area
|
||||
io_registers.a.VIEWPORT = 0
|
||||
| VIEWPORT__y2(191)
|
||||
| VIEWPORT__x2(255)
|
||||
| VIEWPORT__y1(0)
|
||||
| VIEWPORT__x1(0);
|
||||
|
||||
// VTX_10 uses signed 4.6 floating point (10 bit)
|
||||
// | 9 | 8 7 6 | 5 4 3 2 1 0 |
|
||||
// | s | int | decimal |
|
||||
int fixed_point_divisor = 64; // == 2⁶
|
||||
|
||||
// equilateral triangle; centered around the display origin in NDC
|
||||
/*
|
||||
A
|
||||
/ \
|
||||
B---C
|
||||
|
||||
*/
|
||||
|
||||
// fixed point constants; these are converted from floating-point to
|
||||
// integer at compile-time
|
||||
int ax = 0.0 * fixed_point_divisor;
|
||||
int ay = 1.0 * fixed_point_divisor;
|
||||
|
||||
int bx = -0.86602540378 * fixed_point_divisor; // - sqrt(3) / 2
|
||||
int by = -0.5 * fixed_point_divisor;
|
||||
|
||||
int cx = 0.86602540378 * fixed_point_divisor; // + sqrt(3) / 2
|
||||
int cy = -0.5 * fixed_point_divisor;
|
||||
|
||||
int z = 1.0 * fixed_point_divisor;
|
||||
|
||||
// degrees
|
||||
int theta = 0;
|
||||
|
||||
while (1) {
|
||||
// calculate sin/cos for 2d rotation; signed fp20.12 result
|
||||
int cos = cos_fp12(theta);
|
||||
int sin = sin_fp12(theta);
|
||||
|
||||
// load this 4x3 rotation matrix:
|
||||
//
|
||||
// | cos(θ) -sin(θ) 0 |
|
||||
// | sin(θ) cos(θ) 0 |
|
||||
// | 0 0 1 |
|
||||
// | 0 0 0 |
|
||||
//
|
||||
// the 4x3 matrix load order is:
|
||||
//
|
||||
// | 0 1 2 |
|
||||
// | 3 4 5 |
|
||||
// | 6 7 8 |
|
||||
// | 9 a b |
|
||||
|
||||
io_registers.a.MTX_MODE = MTX_MODE__matrix_mode__position;
|
||||
io_registers.a.MTX_LOAD_4X3 = cos; // 0
|
||||
io_registers.a.MTX_LOAD_4X3 = -sin; // 1
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // 2
|
||||
|
||||
io_registers.a.MTX_LOAD_4X3 = sin; // 3
|
||||
io_registers.a.MTX_LOAD_4X3 = cos; // 4
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // 5
|
||||
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // 6
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // 7
|
||||
io_registers.a.MTX_LOAD_4X3 = 1 << 12; // 8
|
||||
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // 9
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // a
|
||||
io_registers.a.MTX_LOAD_4X3 = 0; // b
|
||||
|
||||
// the following vertices are a triangle
|
||||
io_registers.a.BEGIN_VTXS = BEGIN_VTXS__type__triangle;
|
||||
|
||||
io_registers.a.COLOR = COLOR__blue(31);
|
||||
io_registers.a.VTX_10 = 0
|
||||
| VTX_10__z_coordinate(z)
|
||||
| VTX_10__y_coordinate(ay)
|
||||
| VTX_10__x_coordinate(ax);
|
||||
|
||||
io_registers.a.COLOR = COLOR__green(31);
|
||||
io_registers.a.VTX_10 = 0
|
||||
| VTX_10__z_coordinate(z)
|
||||
| VTX_10__y_coordinate(by)
|
||||
| VTX_10__x_coordinate(bx);
|
||||
|
||||
io_registers.a.COLOR = COLOR__red(31);
|
||||
io_registers.a.VTX_10 = 0
|
||||
| VTX_10__z_coordinate(z)
|
||||
| VTX_10__y_coordinate(cy)
|
||||
| VTX_10__x_coordinate(cx);
|
||||
|
||||
// end of the triangle
|
||||
io_registers.a.END_VTXS = 0;
|
||||
|
||||
// wait for the geomtry engine
|
||||
while (io_registers.a.GXSTAT & GXSTAT__geometry_engine_busy);
|
||||
|
||||
// wait for the end of the current frame
|
||||
while (io_registers.a.VCOUNT != 262);
|
||||
while (io_registers.a.VCOUNT == 262);
|
||||
|
||||
// swap buffers
|
||||
io_registers.a.SWAP_BUFFERS = 0;
|
||||
|
||||
// increment theta once per frame
|
||||
theta += 1;
|
||||
if (theta >= 360) {
|
||||
theta = 0;
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
x
Reference in New Issue
Block a user