From 2a131e300cf347f25279f7c9487a22ebcf806bf4 Mon Sep 17 00:00:00 2001
From: Samuel Walker <swalker@piwalker.net>
Date: Thu, 27 Mar 2025 23:27:06 -0600
Subject: [PATCH] drawing a triangle!

---
 main.c | 42 +++++++++++++++++++++++++++++++++---------
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/main.c b/main.c
index 0da54d8..5ba6ce8 100644
--- a/main.c
+++ b/main.c
@@ -1,3 +1,4 @@
+#include "draw_buffers.h"
 #include "draw_primitives.h"
 #include "graph_vram.h"
 #include "gs_psm.h"
@@ -10,6 +11,7 @@
 #include <draw.h>
 #include <stdio.h>
 #include <inttypes.h>
+#include <gs_gp.h>
 
 #ifdef DEBUG
 #define DEBUG_MSG(...) printf(__VA_ARGS__)
@@ -33,6 +35,7 @@ int print_buffer(qword_t *b, int len) {
 int gs_finish() {
     qword_t buff[50];
     qword_t *q = buff;
+    //TODO: Remove!
     q = draw_primitive_xyoffset(q, 0, 0, 0);
     q = draw_finish(q);
     dma_channel_send_normal(DMA_CHANNEL_GIF, buff, q-buff, 0, 0);
@@ -41,13 +44,28 @@ int gs_finish() {
 }
 
 int gs_init(int width, int height, int psm, int psmz, int vmode, int gmode) {
-    int fb_address = graph_vram_allocate(width, height, psm, GRAPH_ALIGN_PAGE);
+    framebuffer_t fb;
+    fb.address = graph_vram_allocate(width, height, psm, GRAPH_ALIGN_PAGE);
+    fb.width = width;
+    fb.height = height;
+    fb.psm = psm;
+    fb.mask = 0;
+    zbuffer_t zb;
+    zb.address = graph_vram_allocate(width, height, psmz, GRAPH_ALIGN_PAGE);
+    zb.enable = 0;
+    zb.method = 0;
+    zb.zsm = psmz;
+    zb.mask = 0;
     graph_set_mode(gmode, vmode, GRAPH_MODE_FIELD, GRAPH_DISABLE);
     graph_set_screen(OFFSET_X, OFFSET_Y, width, height);
     graph_set_bgcolor(0, 0, 0);
-    graph_set_framebuffer_filtered(fb_address, width, psm, 0, 0);
+    graph_set_framebuffer_filtered(fb.address, width, psm, 0, 0);
     graph_enable_output();
-    
+    qword_t buf[100];
+    qword_t *q = buf;
+    q = draw_setup_environment(q, 0, &fb, &zb);
+    dma_channel_send_normal(DMA_CHANNEL_GIF, buf, q-buf, 0, 0);
+    dma_wait_fast();
     gs_finish();
     return 0;
 }
@@ -58,6 +76,8 @@ static int tri[] = {
     20, 400, 0
 };
 
+#define SHIFT_AS_I64(x, b) (((uint64_t)x)<<b);
+
 int draw() {
 
     uint64_t red = 0xf0;
@@ -66,17 +86,21 @@ int draw() {
     qword_t buf[50];
     qword_t *q = buf;
     // GIFTag header - 3x(col, pos)
-    q->dw[0] = 0x6000000000008001;
-    q->dw[1] = 0x0000000000515151;
+    q->dw[0] = 0x7000000000008001;
+    q->dw[1] = 0x0000000005151510;
+    q++;
+
+    q->dw[0] = GS_PRIM_TRIANGLE;
+    q->dw[1] = 0;
     q++;
 
     for(int i = 0; i < 3; i++){
         q->dw[0] = (red&0xff) | (green&0xff)<<32;
-        q->dw[1] = (blue&0xff) | (0x80 << 32);
+        q->dw[1] = (blue&0xff) | SHIFT_AS_I64(0x80, 32);
         q++;
 
-        q->dw[0] = (tri[i+0]<<4) | (tri[i+1]<<4)<<32;
-        q->dw[1] = (tri[i+2]<<4);
+        q->dw[0] = (tri[i*3+0]<<4) | SHIFT_AS_I64(tri[i*3+1]<<4,32);
+        q->dw[1] = (tri[i*3+2]<<4);
         q++;
     }
 
@@ -98,7 +122,7 @@ int main() {
     dma_channel_fast_waits(DMA_CHANNEL_GIF);
     DEBUG_MSG("DMA Initialized...\n");
     // initialize graphics mode
-    gs_init(664, 480, GS_PSM_32, GS_PSMZ_32, GRAPH_MODE_NTSC, GRAPH_MODE_FIELD);
+    gs_init(640, 480, GS_PSM_32, GS_PSMZ_24, GRAPH_MODE_NTSC, GRAPH_MODE_INTERLACED);
     DEBUG_MSG("GS Initialized...\n");
     // clear screen
     draw();