- added immediate mode drawing in 3dgfx

[dosdemo] / src / 3dgfx.c

diff --git a/src/3dgfx.c b/src/3dgfx.c
index c32e6c2..17ddd93 100644 (file)
--- a/src/3dgfx.c
+++ b/src/3dgfx.c
@@ -14,9 +14,10 @@
 #define STACK_SIZE     8
 typedef float g3d_matrix[16];
 
-#define MAX_VBUF_SIZE  256
 #define MAX_LIGHTS             4
 
+#define IMM_VBUF_SIZE  256
+
 struct light {
        float x, y, z;
        float r, g, b;
@@ -47,8 +48,15 @@ struct g3d_state {
        uint16_t *pixels;
 
        int vport[4];
+
+       /* immediate mode */
+       int imm_prim;
+       int imm_numv, imm_pcount;
+       struct g3d_vertex imm_curv;
+       struct g3d_vertex imm_vbuf[IMM_VBUF_SIZE];
 };
 
+static void imm_flush(void);
 static void xform4_vec3(const float *mat, float *vec);
 static void xform3_vec3(const float *mat, float *vec);
 static void shade(struct g3d_vertex *v);
@@ -496,6 +504,94 @@ void g3d_draw_indexed(int prim, const struct g3d_vertex *varr, int varr_size,
        }
 }
 
+void g3d_begin(int prim)
+{
+       st->imm_prim = prim;
+       st->imm_pcount = prim;
+       st->imm_numv = 0;
+}
+
+void g3d_end(void)
+{
+       imm_flush();
+}
+
+static void imm_flush(void)
+{
+       int numv = st->imm_numv;
+       st->imm_numv = 0;
+       g3d_draw_indexed(st->imm_prim, st->imm_vbuf, numv, 0, 0);
+}
+
+void g3d_vertex(float x, float y, float z)
+{
+       struct g3d_vertex *vptr = st->imm_vbuf + st->imm_numv++;
+       *vptr = st->imm_curv;
+       vptr->x = x;
+       vptr->y = y;
+       vptr->z = z;
+       vptr->w = 1.0f;
+
+       if(!--st->imm_pcount) {
+               if(st->imm_numv >= IMM_VBUF_SIZE - st->imm_prim) {
+                       imm_flush();
+               }
+               st->imm_pcount = st->imm_prim;
+       }
+}
+
+void g3d_normal(float x, float y, float z)
+{
+       st->imm_curv.nx = x;
+       st->imm_curv.ny = y;
+       st->imm_curv.nz = z;
+}
+
+void g3d_color3b(unsigned char r, unsigned char g, unsigned char b)
+{
+       st->imm_curv.r = r;
+       st->imm_curv.g = g;
+       st->imm_curv.b = b;
+       st->imm_curv.a = 255;
+}
+
+void g3d_color4b(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
+{
+       st->imm_curv.r = r;
+       st->imm_curv.g = g;
+       st->imm_curv.b = b;
+       st->imm_curv.a = a;
+}
+
+void g3d_color3f(float r, float g, float b)
+{
+       int ir = r * 255.0f;
+       int ig = g * 255.0f;
+       int ib = b * 255.0f;
+       st->imm_curv.r = ir > 255 ? 255 : ir;
+       st->imm_curv.g = ig > 255 ? 255 : ig;
+       st->imm_curv.b = ib > 255 ? 255 : ib;
+       st->imm_curv.a = 255;
+}
+
+void g3d_color4f(float r, float g, float b, float a)
+{
+       int ir = r * 255.0f;
+       int ig = g * 255.0f;
+       int ib = b * 255.0f;
+       int ia = a * 255.0f;
+       st->imm_curv.r = ir > 255 ? 255 : ir;
+       st->imm_curv.g = ig > 255 ? 255 : ig;
+       st->imm_curv.b = ib > 255 ? 255 : ib;
+       st->imm_curv.a = ia > 255 ? 255 : ia;
+}
+
+void g3d_texcoord(float u, float v)
+{
+       st->imm_curv.u = u;
+       st->imm_curv.v = v;
+}
+
 static void xform4_vec3(const float *mat, float *vec)
 {
        float x = mat[0] * vec[0] + mat[4] * vec[1] + mat[8] * vec[2] + mat[12];