//---------------------------------------------------------------------------
void gs_load_texture(u16 x, u16 y, u16 w, u16 h, u32 data_adr, u32 dest_adr, u16 dest_w)
{
u32 i; // DMA buffer loop counter
u32 frac; // flag for whether to run a fractional buffer or not
u32 current; // number of pixels to transfer in current DMA
u32 qtotal; // total number of qwords of data to transfer
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 4, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, bitbltbuf,
GS_BITBLTBUF(0, 0, 0,
dest_adr/256, // frame buffer address
dest_w/64, // frame buffer width
0));
GIF_DATA_AD(gs_dma_buf, trxpos,
GS_TRXPOS(
0,
0,
x,
y,
0)); // left to right/top to bottom
GIF_DATA_AD(gs_dma_buf, trxreg, GS_TRXREG(w, h));
GIF_DATA_AD(gs_dma_buf, trxdir, GS_TRXDIR(XDIR_EE_GS));
SEND_GS_PACKET(gs_dma_buf);
qtotal = w*h/4; // total number of quadwords to transfer.
current = qtotal % MAX_TRANSFER;// work out if a partial buffer transfer is needed.
frac=1; // assume yes.
if(!current) // if there is no need for partial buffer
{
current = MAX_TRANSFER; // start with a full buffer
frac=0; // and don't do extra partial buffer first
}
for(i=0; i<(qtotal/MAX_TRANSFER)+frac; i++)
{
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_IMG(gs_dma_buf, current);
SEND_GS_PACKET(gs_dma_buf);
SET_QWC(GIF_QWC, current);
SET_MADR(GIF_MADR, data_adr, 0);
SET_CHCR(GIF_CHCR, 1, 0, 0, 0, 0, 1, 0);
DMA_WAIT(GIF_CHCR);
data_adr += current*16;
current = MAX_TRANSFER; // after the first one, all are full buffers
}
// Access the TEXFLUSH register with anything to flush the texture
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 1, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, texflush, 0x42);
SEND_GS_PACKET(gs_dma_buf);
}
//---------------------------------------------------------------------------
void g2_fill_rect(s16 x0, s16 y0, s16 x1, s16 y1)
{
x0 += gs_origin_x;
y0 += gs_origin_y;
x1 += gs_origin_x;
y1 += gs_origin_y;
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 4, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, prim,
GS_PRIM(PRIM_SPRITE, 0, 0, 0, 0, 0, 0, 0, 0));
GIF_DATA_AD(gs_dma_buf, rgbaq,
GS_RGBAQ(g2_fill_r, g2_fill_g, g2_fill_b, 0x80, 0));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x0<<4, y0<<4, 0));
// It looks like the default operation for the SPRITE primitive is to
// not draw the right and bottom 'lines' of the rectangle refined by
// the parameters. Add +1 to change this.
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2((x1+1)<<4, (y1+1)<<4, 0));
SEND_GS_PACKET(gs_dma_buf);
}
void gsKit_set_test(GSGLOBAL *gsGlobal, u8 Preset)
{
u64 *p_data;
u64 *p_store;
if(Preset == GS_ZTEST_OFF)
gsGlobal->Test->ZTST = 1;
else if (Preset == GS_ZTEST_ON)
gsGlobal->Test->ZTST = 2;
else if (Preset == GS_ATEST_OFF)
gsGlobal->Test->ATE = 0;
else if (Preset == GS_ATEST_ON)
gsGlobal->Test->ATE = 1;
else if (Preset == GS_D_ATEST_OFF)
gsGlobal->Test->DATE = 0;
else if (Preset == GS_D_ATEST_ON)
gsGlobal->Test->DATE = 1;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1, 16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
*p_data++ = GS_SETREG_TEST( gsGlobal->Test->ATE, gsGlobal->Test->ATST,
gsGlobal->Test->AREF, gsGlobal->Test->AFAIL,
gsGlobal->Test->DATE, gsGlobal->Test->DATM,
gsGlobal->Test->ZTE, gsGlobal->Test->ZTST );
*p_data++ = GS_TEST_1+gsGlobal->PrimContext;
}
//---------------------------------------------------------------------------
void g2_put_image(s16 x, s16 y, s16 w, s16 h, u32 *data)
{
x += gs_origin_x;
y += gs_origin_y;
// - Call this to copy the texture data from EE memory to GS memory.
// - The g2_texbuf_addr variable holds the byte address of the
// 'texture buffer' and is setup in g2_init() to be just after
// the frame buffer(s). When only the standard resolutions are
// used this buffer is guaranteed to be correctly aligned on 256
// bytes.
gs_load_texture(0, 0, w, h, (u32)data, g2_texbuf_addr, g2_max_x+1);
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 6, 1, 0, 0, 0);
// Setup the Texture Buffer register. Note the width and height! They
// must both be a power of 2.
GIF_DATA_AD(gs_dma_buf, tex0_1,
GS_TEX0(
g2_texbuf_addr/256, // base pointer
(g2_max_x+1)/64, // width
0, // 32bit RGBA
gs_texture_wh(w), // width
gs_texture_wh(h), // height
1, // RGBA
TEX_DECAL, // just overwrite existing pixels
0,0,0,0,0));
GIF_DATA_AD(gs_dma_buf, prim,
GS_PRIM(PRIM_SPRITE,
0, // flat shading
1, // texture mapping ON
0, 0, 0, // no fog, alpha, or antialiasing
1, // use UV register for coordinates.
0,
0));
// Texture and vertex coordinates are specified consistently, with
// the last four bits being the decimal part (always X.0 here).
// Top/Left, texture coordinates (0, 0).
GIF_DATA_AD(gs_dma_buf, uv, GS_UV(0, 0));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x<<4, y<<4, 0));
// Bottom/Right, texture coordinates (w, h).
GIF_DATA_AD(gs_dma_buf, uv, GS_UV(w<<4, h<<4));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2((x+w)<<4, (y+h)<<4, 0));
// Finally send the command buffer to the GIF.
SEND_GS_PACKET(gs_dma_buf);
}
void gsKit_set_texfilter(GSGLOBAL *gsGlobal, u8 FilterMode)
{
u64 *p_data;
u64 *p_store;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1, 16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
*p_data++ = GS_SETREG_TEX1(0, 0, FilterMode, FilterMode, 0, 0, 0);
*p_data++ = GS_TEX1_1+gsGlobal->PrimContext;
}
//---------------------------------------------------------------------------
void g2_set_viewport(u16 x0, u16 y0, u16 x1, u16 y1)
{
g2_view_x0 = x0;
g2_view_x1 = x1;
g2_view_y0 = y0;
g2_view_y1 = y1;
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 1, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, scissor_1,
GS_SCISSOR(x0, x1, y0, y1));
SEND_GS_PACKET(gs_dma_buf);
}
//---------------------------------------------------------------------------
void g2_set_active_frame(u8 frame)
{
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 1, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, frame_1,
GS_FRAME(
g2_frame_addr[frame]/8192, // FrameBuffer base pointer = Address/8192
cur_mode->width/64, // Frame buffer width (Pixels/64)
cur_mode->psm, // Pixel Storage Format
0));
SEND_GS_PACKET(gs_dma_buf);
g2_active_frame = frame;
}
void gsKit_set_dither_matrix(GSGLOBAL *gsGlobal)
{
u64 *p_data;
u64 *p_store;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1 ,16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
*p_data++ = GS_SETREG_DIMX( gsGlobal->DitherMatrix[0], gsGlobal->DitherMatrix[1], gsGlobal->DitherMatrix[2], gsGlobal->DitherMatrix[3],
gsGlobal->DitherMatrix[4], gsGlobal->DitherMatrix[5], gsGlobal->DitherMatrix[6], gsGlobal->DitherMatrix[7],
gsGlobal->DitherMatrix[8], gsGlobal->DitherMatrix[9], gsGlobal->DitherMatrix[10], gsGlobal->DitherMatrix[11],
gsGlobal->DitherMatrix[12], gsGlobal->DitherMatrix[13], gsGlobal->DitherMatrix[14], gsGlobal->DitherMatrix[15]);
*p_data++ = GS_DIMX;
}
/*
// taken from libgraph
void gsKit_set_drawfield(GSGLOBAL *gsGlobal, u8 field)
{
u64 *p_data;
u64 *p_store;
(u32)p_data = (u32)p_store = gsGlobal->dma_misc;
*p_data++ = GIF_TAG( 1, 1, 0, 0, 0, 1);
*p_data++ = GIF_AD;
if (field == GS_FIELD_NORMAL) { //Draw both
*p_data++ = GIF_TAG_SCANMSK(0);
}
else if (field == GS_FIELD_ODD) { // Draw only odd
*p_data++ = GIF_TAG_SCANMSK(2);
}
else if (field == GS_FIELD_EVEN) { // Draw only even
*p_data++ = GIF_TAG_SCANMSK(3);
}
*p_data++ = GS_SCANMSK;
dmaKit_wait_fast();
dmaKit_send_ucab(DMA_CHANNEL_GIF, p_store, 2);
}
*/
GSQUEUE gsKit_set_finish(GSGLOBAL *gsGlobal)
{
u64 *p_data;
u64 *p_store;
GSQUEUE oldQueue = *gsGlobal->CurQueue;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1, 16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
*p_data++ = 0;
*p_data++ = GS_FINISH;
return oldQueue;
}
void gsKit_set_dither(GSGLOBAL *gsGlobal)
{
u64 *p_data;
u64 *p_store;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1, 16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
if(gsGlobal->Dithering == GS_SETTING_ON)
*p_data++ = 1;
else
*p_data++ = 0;
*p_data++ = GS_DTHE;
}
//---------------------------------------------------------------------------
void g2_set_font_color(u8 red, u8 green, u8 blue)
{
u64 x0;
u64 y0;
u64 x1;
u64 y1;
x0 = gs_origin_x-10;
y0 = gs_origin_y-10;
x1 = g2_fontbuf_w + gs_origin_x;
y1 = g2_fontbuf_h + gs_origin_y;
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 6, 1, 0, 0, 0);
// Restore the frame buffer to the current active frame buffer.
GIF_DATA_AD(gs_dma_buf, frame_1,
GS_FRAME(
g2_fontbuf_addr/8192,
cur_mode->width/64,
cur_mode->psm,
0));
// Draw the colored rectangle over the entire Font Bitmap.
GIF_DATA_AD(gs_dma_buf, prim,
GS_PRIM(PRIM_LINE, 0, 0, 0, 0, 0, 0, 0, 0));
// GS_PRIM(PRIM_SPRITE, 0, 0, 0, 0, 0, 0, 0, 0));
GIF_DATA_AD(gs_dma_buf, rgbaq,
GS_RGBAQ(red, green, blue, 0x80, 0));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x0<<4, y0<<4, 0));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x1<<4, y1<<4, 0));
// Restore the frame buffer to the current active frame buffer.
GIF_DATA_AD(gs_dma_buf, frame_1,
GS_FRAME(
g2_frame_addr[g2_active_frame]/8192,
cur_mode->width/64,
cur_mode->psm,
0));
SEND_GS_PACKET(gs_dma_buf);
}
void gsKit_set_primalpha(GSGLOBAL *gsGlobal, u64 AlphaMode, u8 PerPixel)
{
u64 *p_data;
u64 *p_store;
gsGlobal->PrimAlpha = AlphaMode;
gsGlobal->PABE = PerPixel;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 2, 32, GIF_AD);
*p_data++ = GIF_TAG_AD(2);
*p_data++ = GIF_AD;
*p_data++ = gsGlobal->PABE;
*p_data++ = GS_PABE;
*p_data++ = gsGlobal->PrimAlpha;
*p_data++ = GS_ALPHA_1+gsGlobal->PrimContext;
}
//---------------------------------------------------------------------------
void g2_line(s16 x0, s16 y0, s16 x1, s16 y1)
{
x0 += gs_origin_x;
y0 += gs_origin_y;
x1 += gs_origin_x;
y1 += gs_origin_y;
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 4, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, prim,
GS_PRIM(PRIM_LINE, 0, 0, 0, 0, 0, 0, 0, 0));
GIF_DATA_AD(gs_dma_buf, rgbaq,
GS_RGBAQ(g2_col_r, g2_col_g, g2_col_b, 0x80, 0));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x0<<4, y0<<4, 0));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x1<<4, y1<<4, 0));
SEND_GS_PACKET(gs_dma_buf);
}
//---------------------------------------------------------------------------
void g2_put_pixel(s16 x, s16 y)
{
x += gs_origin_x;
y += gs_origin_y;
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 4, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, prim,
GS_PRIM(PRIM_POINT, 0, 0, 0, 0, 0, 0, 0, 0));
GIF_DATA_AD(gs_dma_buf, rgbaq,
GS_RGBAQ(g2_col_r, g2_col_g, g2_col_b, 0x80, 0));
// The XYZ coordinates are actually floating point numbers between
// 0 and 4096 represented as unsigned integers where the lowest order
// four bits are the fractional point. That's why all coordinates are
// shifted left 4 bits.
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x<<4, y<<4, 0));
SEND_GS_PACKET(gs_dma_buf);
}
// taken from libgraph
void gsKit_set_drawfield(GSGLOBAL *gsGlobal, u8 field)
{
u64 *p_data;
u64 *p_store;
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1 ,16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
if (field == GS_FIELD_NORMAL) { //Draw both
*p_data++ = 0;;
}
else if (field == GS_FIELD_ODD) { // Draw only odd
*p_data++ = 2;
}
else if (field == GS_FIELD_EVEN) { // Draw only even
*p_data++ = 3;
}
*p_data++ = GS_SCANMSK;
}
void gsKit_set_clamp(GSGLOBAL *gsGlobal, u8 Preset)
{
u64 *p_data;
u64 *p_store;
if(Preset == GS_CMODE_REPEAT)
{
gsGlobal->Clamp->WMS = GS_CMODE_REPEAT;
gsGlobal->Clamp->WMT = GS_CMODE_REPEAT;
}
else if(Preset == GS_CMODE_CLAMP)
{
gsGlobal->Clamp->WMS = GS_CMODE_CLAMP;
gsGlobal->Clamp->WMT = GS_CMODE_CLAMP;
}
else if(Preset == GS_CMODE_REGION_CLAMP)
{
gsGlobal->Clamp->WMS = GS_CMODE_REGION_CLAMP;
gsGlobal->Clamp->WMT = GS_CMODE_REGION_CLAMP;
}
else if(Preset == GS_CMODE_REGION_REPEAT)
{
gsGlobal->Clamp->WMS = GS_CMODE_REGION_REPEAT;
gsGlobal->Clamp->WMT = GS_CMODE_REGION_REPEAT;
}
p_data = p_store = gsKit_heap_alloc(gsGlobal, 1, 16, GIF_AD);
*p_data++ = GIF_TAG_AD(1);
*p_data++ = GIF_AD;
*p_data++ = GS_SETREG_CLAMP(gsGlobal->Clamp->WMS, gsGlobal->Clamp->WMT,
gsGlobal->Clamp->MINU, gsGlobal->Clamp->MAXU,
gsGlobal->Clamp->MINV, gsGlobal->Clamp->MAXV);
*p_data++ = GS_CLAMP_1+gsGlobal->PrimContext;
}
//---------------------------------------------------------------------------
void g2_out_text(s16 x, s16 y, char *str)
{
char c; // current character
u16 *tc; // current texture coordinates [4]
u16 x0, y0, x1, y1; // rectangle for current character
u16 w, h; // width and height of above rectangle
x += gs_origin_x;
y += gs_origin_y;
c = *str;
while(c)
{
// Read the texture coordinates for current character
tc = &g2_font_tc[c*4];
x0 = *tc++;
y0 = *tc++;
x1 = *tc++;
y1 = *tc++;
w = x1-x0+1;
h = y1-y0+1;
// Draw a sprite with current character mapped onto it
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 6, 1, 0, 0, 0);
GIF_DATA_AD(gs_dma_buf, tex0_1,
GS_TEX0(
g2_fontbuf_addr/256, // base pointer
(g2_fontbuf_w)/64, // width
0, // 32bit RGBA
gs_texture_wh(g2_fontbuf_w),// width
gs_texture_wh(g2_fontbuf_w),// height
1, // RGBA
TEX_DECAL, // just overwrite existing pixels
0,0,0,0,0));
/*
GIF_DATA_AD(gs_dma_buf, tex1_1,
GS_TEX1(
0, 0,
FILTER_LINEAR,
FILTER_LINEAR,
0, 0, 0));
GIF_DATA_AD(gs_dma_buf, clamp_1, 0x05);
*/
GIF_DATA_AD(gs_dma_buf, prim,
GS_PRIM(PRIM_SPRITE,
0, // flat shading
1, // texture mapping ON
0, 1, 0, // no fog or antialiasing, but use alpha
1, // use UV register for coordinates.
0,
0));
GIF_DATA_AD(gs_dma_buf, uv, GS_UV(x0<<4, y0<<4));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(x<<4, y<<4, 0));
GIF_DATA_AD(gs_dma_buf, uv, GS_UV((x1+1)<<4, (y1+1)<<4));
GIF_DATA_AD(gs_dma_buf, xyz2, GS_XYZ2(
(x+w*g2_font_mag)<<4, (y+h*g2_font_mag)<<4, 0));
SEND_GS_PACKET(gs_dma_buf);
// Advance drawing position
x += (w + g2_font_spacing) * g2_font_mag;
// Get next character
str++;
c = *str;
}
}
//---------------------------------------------------------------------------
int g2_init(g2_video_mode mode)
{
vmode_t *v;
v = &(vmodes[mode]);
cur_mode = v;
g2_max_x = v->width - 1;
g2_max_y = v->height - 1;
g2_view_x0 = 0;
g2_view_y0 = 0;
g2_view_x1 = g2_max_x;
g2_view_y1 = g2_max_y;
gs_origin_x = 1024;
gs_origin_y = 1024;
gs_mem_current = 0; // nothing allocated yet
g2_visible_frame = 0; // display frame 0
g2_active_frame = 0; // draw to frame 0
// - Initialize the DMA.
// - Writes a 0 to most of the DMA registers.
dma_reset();
// - Sets the RESET bit if the GS CSR register.
GS_RESET();
#ifndef FLASH
// - Can someone please tell me what the sync.p
// instruction does. Synchronizes something :-)
__asm__("
sync.p
nop
");
#endif
// - Sets up the GS IMR register (i guess).
// - The IMR register is used to mask and unmask certain interrupts,
// for example VSync and HSync. We'll use this properly in Tutorial 2.
// - Does anyone have code to do this without using the 0x71 syscall?
// - I havn't gotten around to looking at any PS2 bios code yet.
gs_set_imr();
// - Use syscall 0x02 to setup some video mode stuff.
// - Pretty self explanatory I think.
// - Does anyone have code to do this without using the syscall? It looks
// like it should only set the SMODE2 register, but if I remove this syscall
// and set the SMODE2 register myself, it donesn't work. What else does
// syscall 0x02 do?
gs_set_crtc(NON_INTERLACED, v->ntsc_pal, FRAME);
// - I havn't attempted to understand what the Alpha parameters can do. They
// have been blindly copied from the 3stars demo (although they don't seem
// do have any impact in this simple 2D code.
GS_SET_PMODE(
0, // ReadCircuit1 OFF
1, // ReadCircuit2 ON
1, // Use ALP register for Alpha Blending
1, // Alpha Value of ReadCircuit2 for output selection
0, // Blend Alpha with the output of ReadCircuit2
0xFF // Alpha Value = 1.0
);
/*
// - Non needed if we use gs_set_crt()
GS_SET_SMODE2(
0, // Non-Interlaced mode
1, // FRAME mode (read every line)
0 // VESA DPMS Mode = ON ??? please explain ???
);
*/
GS_SET_DISPFB2(
0, // Frame Buffer base pointer = 0 (Address/8192)
v->width/64, // Buffer Width (Pixels/64)
v->psm, // Pixel Storage Format
0, // Upper Left X in Buffer = 0
0 // Upper Left Y in Buffer = 0
);
// Why doesn't (0, 0) equal the very top-left of the TV?
GS_SET_DISPLAY2(
656, // X position in the display area (in VCK units)
36, // Y position in the display area (in Raster units)
v->magh-1, // Horizontal Magnification - 1
0, // Vertical Magnification = 1x
v->width*v->magh-1, // Display area width - 1 (in VCK units) (Width*HMag-1)
v->height-1 // Display area height - 1 (in pixels) (Height-1)
);
GS_SET_BGCOLOR(
0, // RED
0, // GREEN
0 // BLUE
);
BEGIN_GS_PACKET(gs_dma_buf);
GIF_TAG_AD(gs_dma_buf, 6, 1, 0, 0, 0);
// Use drawing parameters from PRIM register
GIF_DATA_AD(gs_dma_buf, prmodecont, 1);
// Setup frame buffers. Point to 0 initially.
GIF_DATA_AD(gs_dma_buf, frame_1,
GS_FRAME(
0, // FrameBuffer base pointer = 0 (Address/8192)
v->width/64, // Frame buffer width (Pixels/64)
v->psm, // Pixel Storage Format
0));
// Save address and advance GS memory pointer by buffer size (in bytes)
// Do this for both frame buffers.
g2_frame_addr[0] = gs_mem_current;
gs_mem_current += v->width * v->height * (v->bpp/8);
g2_frame_addr[1] = gs_mem_current;
gs_mem_current += v->width * v->height * (v->bpp/8);
// Displacement between Primitive and Window coordinate systems.
GIF_DATA_AD(gs_dma_buf, xyoffset_1,
GS_XYOFFSET(
gs_origin_x<<4,
gs_origin_y<<4));
// Clip to frame buffer.
GIF_DATA_AD(gs_dma_buf, scissor_1,
GS_SCISSOR(
0,
g2_max_x,
0,
g2_max_y));
// Create a single 256x128 font buffer
g2_fontbuf_addr = gs_mem_current;
gs_mem_current += g2_fontbuf_w * g2_fontbuf_h * (v->bpp/8);
// Create a texture buffer as big as the screen.
// Just save the address advance GS memory pointer by buffer size (in bytes)
// The TEX registers are set later, when drawing.
g2_texbuf_addr = gs_mem_current;
gs_mem_current += v->width * v->height * (v->bpp/8);
// Setup test_1 register to allow transparent texture regions where A=0
GIF_DATA_AD(gs_dma_buf, test_1,
GS_TEST(
1, // Alpha Test ON
ATST_NOTEQUAL, 0x00, // Reject pixels with A=0
AFAIL_KEEP, // Don't update frame or Z buffers
0, 0, 0, 0)); // No Destination Alpha or Z-Buffer Tests
// Setup the ALPHA_1 register to correctly blend edges of
// pre-antialiased fonts using Alpha Blending stage.
// The blending formula is
// PIXEL=(SRC-FRAME)*SRC_ALPHA>>7+FRAME
GIF_DATA_AD(gs_dma_buf, alpha_1,
GS_ALPHA(
0, // A - source
1, // B - frame buffer
0, // C - alpha from source
1, // D - frame buffer
0)); // FIX - not needed
SEND_GS_PACKET(gs_dma_buf);
return(1);
}
