nuclear@1: #include <stdlib.h>
nuclear@5: #include <string.h>
nuclear@5: #include <math.h>
nuclear@1: #include "min3d.h"
nuclear@1: #include "m3dimpl.h"
nuclear@1: 
nuclear@1: #ifndef M_PI
nuclear@1: #define M_PI	3.141592653
nuclear@1: #endif
nuclear@1: 
nuclear@3: struct min3d_context *m3dctx;
nuclear@3: 
nuclear@1: int m3d_init(void)
nuclear@1: {
nuclear@1: 	if(!(m3dctx = malloc(sizeof *m3dctx))) {
nuclear@1: 		return -1;
nuclear@1: 	}
nuclear@1: 	memset(m3dctx, 0, sizeof *m3dctx);
nuclear@1: 
nuclear@1: 	m3d_matrix_mode(M3D_PROJECTION);
nuclear@1: 	m3d_load_identity();
nuclear@1: 	m3d_matrix_mode(M3D_MODELVIEW);
nuclear@1: 	m3d_load_identity();
nuclear@1: 	return 0;
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_shutdown(void)
nuclear@1: {
nuclear@1: 	free(m3dctx);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_set_buffers(struct m3d_image *cbuf, uint16_t *zbuf)
nuclear@1: {
nuclear@1: 	m3dctx->cbuf = cbuf;
nuclear@1: 	m3dctx->zbuf = zbuf;
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_clear(unsigned int bmask)
nuclear@1: {
nuclear@1: 	int num_pixels = m3dctx->cbuf->xsz * m3dctx->cbuf->ysz;
nuclear@1: 	if(bmask & M3D_COLOR_BUFFER_BIT) {
nuclear@1: 		memset(m3dctx->cbuf->pixels, 0, num_pixels * 3);
nuclear@1: 	}
nuclear@1: 	if(bmask & M3D_DEPTH_BUFFER_BIT) {
nuclear@1: 		memset(m3dctx->zbuf, 0xff, num_pixels * sizeof *m3dctx->zbuf);
nuclear@1: 	}
nuclear@1: }
nuclear@1: 
nuclear@1: 
nuclear@1: void m3d_enable(int bit)
nuclear@1: {
nuclear@1: 	m3dctx->state |= (1 << bit);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_disable(int bit)
nuclear@1: {
nuclear@1: 	m3dctx->state &= ~(1 << bit);
nuclear@1: }
nuclear@1: 
nuclear@1: 
nuclear@1: /* matrix stack */
nuclear@1: void m3d_matrix_mode(int mode)
nuclear@1: {
nuclear@1: 	m3dctx->mmode = mode;
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_load_identity(void)
nuclear@1: {
nuclear@1: 	static const float mid[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@1: 	m3d_load_matrix(mid);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_load_matrix(const float *m)
nuclear@1: {
nuclear@1: 	int top = m3dctx->mstack[m3dctx->mmode].top;
nuclear@1: 	memcpy(m3dctx->mstack[m3dctx->mmode].m[top], m, 16 * sizeof *m);
nuclear@1: }
nuclear@1: 
nuclear@1: #define M(i,j)	(((i) << 2) + (j))
nuclear@1: void m3d_mult_matrix(const float *m2)
nuclear@1: {
nuclear@1: 	int i, j, top = m3dctx->mstack[m3dctx->mmode].top;
nuclear@1: 	float m1[16];
nuclear@1: 	float *dest = m3dctx->mstack[m3dctx->mmode].m[top];
nuclear@1: 
nuclear@1: 	memcpy(m1, dest, sizeof m1);
nuclear@1: 
nuclear@1: 	for(i=0; i<4; i++) {
nuclear@1: 		for(j=0; j<4; j++) {
nuclear@1: 			dest[M(i,j)] = m1[M(0,j)] * m2[M(i,0)] +
nuclear@1: 				m1[M(1,j)] * m2[M(i,1)] +
nuclear@1: 				m1[M(2,j)] * m2[M(i,2)] +
nuclear@1: 				m1[M(3,j)] * m2[M(i,3)];
nuclear@1: 		}
nuclear@1: 	}
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_translate(float x, float y, float z)
nuclear@1: {
nuclear@1: 	float m[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@1: 	m[12] = x;
nuclear@1: 	m[13] = y;
nuclear@1: 	m[14] = z;
nuclear@1: 	m3d_mult_matrix(m);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_rotate(float deg, float x, float y, float z)
nuclear@1: {
nuclear@1: 	float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@1: 
nuclear@1: 	float angle = M_PI * deg / 180.0f;
nuclear@1: 	float sina = sin(angle);
nuclear@1: 	float cosa = cos(angle);
nuclear@1: 	float one_minus_cosa = 1.0f - cosa;
nuclear@1: 	float nxsq = x * x;
nuclear@1: 	float nysq = y * y;
nuclear@1: 	float nzsq = z * z;
nuclear@1: 
nuclear@1: 	xform[0] = nxsq + (1.0f - nxsq) * cosa;
nuclear@1: 	xform[4] = x * y * one_minus_cosa - z * sina;
nuclear@1: 	xform[8] = x * z * one_minus_cosa + y * sina;
nuclear@1: 	xform[1] = x * y * one_minus_cosa + z * sina;
nuclear@1: 	xform[5] = nysq + (1.0 - nysq) * cosa;
nuclear@1: 	xform[9] = y * z * one_minus_cosa - x * sina;
nuclear@1: 	xform[2] = x * z * one_minus_cosa - y * sina;
nuclear@1: 	xform[6] = y * z * one_minus_cosa + x * sina;
nuclear@1: 	xform[10] = nzsq + (1.0 - nzsq) * cosa;
nuclear@1: 
nuclear@1: 	m3d_mult_matrix(xform);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_scale(float x, float y, float z)
nuclear@1: {
nuclear@1: 	static float m[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@1: 	m[0] = x;
nuclear@1: 	m[5] = y;
nuclear@1: 	m[10] = z;
nuclear@1: 	m3d_mult_matrix(m);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_frustum(float left, float right, float bottom, float top, float nr, float fr)
nuclear@1: {
nuclear@1: 	float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@1: 
nuclear@1: 	float dx = right - left;
nuclear@1: 	float dy = top - bottom;
nuclear@1: 	float dz = fr - nr;
nuclear@1: 
nuclear@1: 	float a = (right + left) / dx;
nuclear@1: 	float b = (top + bottom) / dy;
nuclear@1: 	float c = -(fr + nr) / dz;
nuclear@1: 	float d = -2.0 * fr * nr / dz;
nuclear@1: 
nuclear@1: 	xform[0] = 2.0 * nr / dx;
nuclear@1: 	xform[5] = 2.0 * nr / dy;
nuclear@1: 	xform[8] = a;
nuclear@1: 	xform[9] = b;
nuclear@1: 	xform[10] = c;
nuclear@1: 	xform[11] = -1.0f;
nuclear@1: 	xform[14] = d;
nuclear@1: 
nuclear@1: 	m3d_mult_matrix(xform);
nuclear@1: }
nuclear@1: 
nuclear@1: void m3d_perspective(float vfov, float aspect, float nr, float fr)
nuclear@1: {
nuclear@1: 	float vfov_rad = M_PI * vfov / 180.0;
nuclear@1: 	float x = nr * tan(vfov_rad / 2.0);
nuclear@1: 	m3d_frustum(-aspect * x, aspect * x, -x, x, nr, fr);
nuclear@1: }
nuclear@1: 
nuclear@2: static void xform4(float *mat, float *vec)
nuclear@2: {
nuclear@2: 	float x = mat[0] * vec[0] + mat[1] * vec[1] + mat[2] * vec[2] + mat[3];
nuclear@2: 	float y = mat[4] * vec[0] + mat[5] * vec[1] + mat[6] * vec[2] + mat[7];
nuclear@2: 	float z = mat[8] * vec[0] + mat[9] * vec[1] + mat[10] * vec[2] + mat[11];
nuclear@2: 	float w = mat[12] * vec[0] + mat[13] * vec[1] + mat[14] * vec[2] + mat[15];
nuclear@2: 
nuclear@2: 	vec[0] = x;
nuclear@2: 	vec[1] = y;
nuclear@2: 	vec[2] = z;
nuclear@2: 	vec[3] = w;
nuclear@2: }
nuclear@2: 
nuclear@3: static int proc_prim(int prim, struct min3d_vertex *res, struct min3d_vertex *v)
nuclear@2: {
nuclear@3: 	int i;
nuclear@3: 	int vcount = prim;
nuclear@3: 	int mvtop, ptop;
nuclear@3: 	float *mvmat, *pmat;
nuclear@3: 
nuclear@3: 	mvtop = m3dctx->mstack[M3D_MODELVIEW].top;
nuclear@3: 	mvmat = m3dctx->mstack[M3D_MODELVIEW].m[mvtop];
nuclear@3: 	ptop = m3dctx->mstack[M3D_PROJECTION].top;
nuclear@3: 	pmat = m3dctx->mstack[M3D_PROJECTION].m[ptop];
nuclear@3: 
nuclear@3: 	/* transform to view space */
nuclear@3: 	for(i=0; i<vcount; i++) {
nuclear@3: 		res[i] = v[i];
nuclear@3: 		xform4(mvmat, res[i].pos);
nuclear@3: 		/* TODO: normal */
nuclear@3: 	}
nuclear@3: 
nuclear@3: 	/* TODO: lighting */
nuclear@3: 
nuclear@3: 	/* project */
nuclear@3: 	for(i=0; i<vcount; i++) {
nuclear@3: 		xform4(pmat, res[i].pos);
nuclear@3: 	}
nuclear@3: 
nuclear@3: 	/* clip */
nuclear@3: 	switch(prim) {
nuclear@3: 	case M3D_POINTS:
nuclear@3: 		{
nuclear@3: 			float w = res[0].pos[3];
nuclear@3: 			if(res[0].pos[2] < -w || res[0].pos[2] >= w ||
nuclear@3: 					res[0].pos[0] / w < -1 || res[0].pos[0] / w >= 1 ||
nuclear@3: 					res[0].pos[1] / w < -1 || res[0].pos[1] / w >= 1) {
nuclear@3: 				vcount = 0;
nuclear@3: 			}
nuclear@3: 		}
nuclear@3: 		break;
nuclear@3: 
nuclear@3: 	default:
nuclear@3: 		break;	/* TODO */
nuclear@3: 	}
nuclear@3: 
nuclear@3: 	/* perspective division */
nuclear@3: 	for(i=0; i<vcount; i++) {
nuclear@3: 		res[i].pos[0] = res[i].pos[3];
nuclear@3: 		res[i].pos[1] = res[i].pos[3];
nuclear@3: 		res[i].pos[2] = res[i].pos[3];
nuclear@3: 	}
nuclear@3: 	return vcount;
nuclear@2: }
nuclear@2: 
nuclear@1: /* drawing */
nuclear@5: void m3d_vertex_array(const float *varr)
nuclear@5: {
nuclear@5: 	m3dctx->vert_array = varr;
nuclear@5: }
nuclear@5: 
nuclear@5: void m3d_normal_array(const float *narr)
nuclear@5: {
nuclear@5: 	m3dctx->norm_array = narr;
nuclear@5: }
nuclear@5: 
nuclear@5: void m3d_color_array(const float *carr)
nuclear@5: {
nuclear@5: 	m3dctx->col_array = carr;
nuclear@5: }
nuclear@5: 
nuclear@5: void m3d_texcoord_array(const float *tcarr)
nuclear@5: {
nuclear@5: 	m3dctx->tc_array = tcarr;
nuclear@5: }
nuclear@5: 
nuclear@5: 
nuclear@5: void m3d_draw(int prim, int vcount)
nuclear@1: {
nuclear@3: 	int i;
nuclear@3: 	struct min3d_vertex v[4];
nuclear@3: 	struct min3d_vertex resv[16];
nuclear@5: 	const float *varr = m3dctx->vert_array;
nuclear@5: 	const float *carr = m3dctx->col_array;
nuclear@5: 
nuclear@5: 	if(!varr) return;
nuclear@3: 
nuclear@3: 	for(i=0; i<vcount; i++) {
nuclear@3: 		int idx = i % prim;
nuclear@3: 
nuclear@3: 		v[idx].pos[0] = *varr++;
nuclear@3: 		v[idx].pos[1] = *varr++;
nuclear@3: 		v[idx].pos[2] = *varr++;
nuclear@5: 		v[idx].color[0] = carr ? *carr++ : m3dctx->cur_color[0];
nuclear@5: 		v[idx].color[1] = carr ? *carr++ : m3dctx->cur_color[1];
nuclear@5: 		v[idx].color[2] = carr ? *carr++ : m3dctx->cur_color[2];
nuclear@3: 
nuclear@3: 		if(idx == prim - 1) {
nuclear@3: 			int resnum = proc_prim(prim, resv, v);
nuclear@3: 			switch(resnum) {
nuclear@3: 			case 1:
nuclear@3: 				draw_point(resv);
nuclear@3: 				break;
nuclear@3: 
nuclear@3: 			case '2':
nuclear@3: 				draw_line(resv);
nuclear@3: 				break;
nuclear@3: 
nuclear@3: 			default:
nuclear@3: 				draw_poly(resv, resnum);
nuclear@3: 			}
nuclear@3: 		}
nuclear@3: 	}
nuclear@1: }
nuclear@1: 
nuclear@5: void m3d_draw_indexed(int prim, const int *idxarr, int icount)
nuclear@1: {
nuclear@1: 	/* TODO */
nuclear@1: }
nuclear@1: