ref: 8a2faea87198104c3f8360a09d126a61e70fecd2
dir: /src/matrix.c/
#include "zgl.h" void gl_print_matrix( const float *m) { int i; for (i=0;i<4;i++) { fprintf(stderr,"%f %f %f %f\n", m[i], m[4+i], m[8+i], m[12+i] ); } } static inline void gl_matrix_update(GLContext *c) { c->matrix_model_projection_updated=(c->matrix_mode<=1); } void glopMatrixMode(GLContext *c,GLParam *p) { int mode=p[1].i; switch(mode) { case GL_MODELVIEW: c->matrix_mode=0; break; case GL_PROJECTION: c->matrix_mode=1; break; case GL_TEXTURE: c->matrix_mode=2; break; default: assert(0); } } void glopLoadMatrix(GLContext *c,GLParam *p) { M4 *m; int i; GLParam *q; m=c->matrix_stack_ptr[c->matrix_mode]; q=p+1; for(i=0;i<4;i++) { m->m[0][i]=q[0].f; m->m[1][i]=q[1].f; m->m[2][i]=q[2].f; m->m[3][i]=q[3].f; q+=4; } gl_matrix_update(c); } void glopLoadIdentity(GLContext *c,GLParam *p) { gl_M4_Id(c->matrix_stack_ptr[c->matrix_mode]); gl_matrix_update(c); } void glopMultMatrix(GLContext *c,GLParam *p) { M4 m; int i; GLParam *q; q=p+1; for(i=0;i<4;i++) { m.m[0][i]=q[0].f; m.m[1][i]=q[1].f; m.m[2][i]=q[2].f; m.m[3][i]=q[3].f; q+=4; } gl_M4_MulLeft(c->matrix_stack_ptr[c->matrix_mode],&m); gl_matrix_update(c); } void glopPushMatrix(GLContext *c,GLParam *p) { int n=c->matrix_mode; M4 *m; assert( (c->matrix_stack_ptr[n] - c->matrix_stack[n] + 1 ) < c->matrix_stack_depth_max[n] ); m=++c->matrix_stack_ptr[n]; gl_M4_Move(&m[0],&m[-1]); gl_matrix_update(c); } void glopPopMatrix(GLContext *c,GLParam *p) { int n=c->matrix_mode; assert( c->matrix_stack_ptr[n] > c->matrix_stack[n] ); c->matrix_stack_ptr[n]--; gl_matrix_update(c); } void glopRotate(GLContext *c,GLParam *p) { M4 m; float u[3]; float angle; int dir_code; angle = p[1].f * M_PI / 180.0; u[0]=p[2].f; u[1]=p[3].f; u[2]=p[4].f; /* simple case detection */ dir_code = ((u[0] != 0)<<2) | ((u[1] != 0)<<1) | (u[2] != 0); switch(dir_code) { case 0: gl_M4_Id(&m); break; case 4: if (u[0] < 0) angle=-angle; gl_M4_Rotate(&m,angle,0); break; case 2: if (u[1] < 0) angle=-angle; gl_M4_Rotate(&m,angle,1); break; case 1: if (u[2] < 0) angle=-angle; gl_M4_Rotate(&m,angle,2); break; default: { float cost, sint; /* normalize vector */ float len = u[0]*u[0]+u[1]*u[1]+u[2]*u[2]; if (len == 0.0f) return; len = 1.0f / sqrt(len); u[0] *= len; u[1] *= len; u[2] *= len; /* store cos and sin values */ cost=cos(angle); sint=sin(angle); /* fill in the values */ m.m[3][0]=m.m[3][1]=m.m[3][2]= m.m[0][3]=m.m[1][3]=m.m[2][3]=0.0f; m.m[3][3]=1.0f; /* do the math */ m.m[0][0]=u[0]*u[0]+cost*(1-u[0]*u[0]); m.m[1][0]=u[0]*u[1]*(1-cost)-u[2]*sint; m.m[2][0]=u[2]*u[0]*(1-cost)+u[1]*sint; m.m[0][1]=u[0]*u[1]*(1-cost)+u[2]*sint; m.m[1][1]=u[1]*u[1]+cost*(1-u[1]*u[1]); m.m[2][1]=u[1]*u[2]*(1-cost)-u[0]*sint; m.m[0][2]=u[2]*u[0]*(1-cost)-u[1]*sint; m.m[1][2]=u[1]*u[2]*(1-cost)+u[0]*sint; m.m[2][2]=u[2]*u[2]+cost*(1-u[2]*u[2]); } } gl_M4_MulLeft(c->matrix_stack_ptr[c->matrix_mode],&m); gl_matrix_update(c); } void glopScale(GLContext *c,GLParam *p) { float *m; float x=p[1].f,y=p[2].f,z=p[3].f; m=&c->matrix_stack_ptr[c->matrix_mode]->m[0][0]; m[0] *= x; m[1] *= y; m[2] *= z; m[4] *= x; m[5] *= y; m[6] *= z; m[8] *= x; m[9] *= y; m[10] *= z; m[12] *= x; m[13] *= y; m[14] *= z; gl_matrix_update(c); } void glopTranslate(GLContext *c,GLParam *p) { float *m; float x=p[1].f,y=p[2].f,z=p[3].f; m=&c->matrix_stack_ptr[c->matrix_mode]->m[0][0]; m[3] = m[0] * x + m[1] * y + m[2] * z + m[3]; m[7] = m[4] * x + m[5] * y + m[6] * z + m[7]; m[11] = m[8] * x + m[9] * y + m[10] * z + m[11]; m[15] = m[12] * x + m[13] * y + m[14] * z + m[15]; gl_matrix_update(c); } void glopFrustum(GLContext *c,GLParam *p) { float *r; M4 m; float left=p[1].f; float right=p[2].f; float bottom=p[3].f; float top=p[4].f; float near=p[5].f; float farp=p[6].f; float x,y,A,B,C,D; x = (2.0*near) / (right-left); y = (2.0*near) / (top-bottom); A = (right+left) / (right-left); B = (top+bottom) / (top-bottom); C = -(farp+near) / ( farp-near); D = -(2.0*farp*near) / (farp-near); r=&m.m[0][0]; r[0]= x; r[1]=0; r[2]=A; r[3]=0; r[4]= 0; r[5]=y; r[6]=B; r[7]=0; r[8]= 0; r[9]=0; r[10]=C; r[11]=D; r[12]= 0; r[13]=0; r[14]=-1; r[15]=0; gl_M4_MulLeft(c->matrix_stack_ptr[c->matrix_mode],&m); gl_matrix_update(c); }