invisible: src/tesquad.cc annotate

invisible

quick backup

author	Eleni Maria Stea <eleni@mutantstargoat.com>
date	Sun, 10 Nov 2013 14:02:36 +0200
parents
children	b50ad2711f5f

rev	line source
eleni@19	1 #include <GL/gl.h>
eleni@19	2 #include "tesquad.h"
eleni@19	3
eleni@19	4 void draw_tess_quad(float x, float y, float w, float h, int usub, int vsub, bool ortho)
eleni@19	5 {
eleni@19	6 if(ortho) {
eleni@19	7 glPushAttrib(GL_ENABLE_BIT);
eleni@19	8 glDisable(GL_DEPTH_TEST);
eleni@19	9 glDisable(GL_LIGHTING);
eleni@19	10
eleni@19	11 glMatrixMode(GL_PROJECTION);
eleni@19	12 glPushMatrix();
eleni@19	13 glLoadIdentity();
eleni@19	14 }
eleni@19	15
eleni@19	16 float du = 1.0 / usub;
eleni@19	17 float dv = 1.0 / vsub;
eleni@19	18
eleni@19	19 float dx = du * w;
eleni@19	20 float dy = dv * h;
eleni@19	21
eleni@19	22 glBegin(GL_QUADS);
eleni@19	23 for (int i=0; i<vsub; i++) {
eleni@19	24 for (int j=0; j<usub; j++) {
eleni@19	25 float u = j * du;
eleni@19	26 float v = 1.0 - i * dv;
eleni@19	27 float sx = x + j * dx;
eleni@19	28 float sy = y + i * dy;
eleni@19	29
eleni@19	30 glTexCoord2f(u, v);
eleni@19	31 glVertex2f(sx, sy);
eleni@19	32 glTexCoord2f(u + du, v);
eleni@19	33 glVertex2f(sx + dx, sy);
eleni@19	34 glTexCoord2f(u + du, v - dv);
eleni@19	35 glVertex2f(sx + dx, sy + dy);
eleni@19	36 glTexCoord2f(u, v - dv);
eleni@19	37 glVertex2f(sx, sy + dy);
eleni@19	38 }
eleni@19	39 }
eleni@19	40 glEnd();
eleni@19	41
eleni@19	42 if(ortho) {
eleni@19	43 glPopMatrix();
eleni@19	44 glPopAttrib();
eleni@19	45 }
eleni@19	46 }