394889/s_triangle.i.15

   1 static __inline__ int IS_INF_OR_NAN(float x)
   2 {
   3         union {
   4                 float f;
   5                 int i;
   6         } tmp;
   7         tmp.f = x;
   8         return tmp.i;
   9 }
  10
  11 typedef struct {
  12         float **attrib;
  13 } SWvertex;
  14 typedef struct sw_span {
  15         int x;
  16         int y;
  17         int end;
  18         float attrStepX[30][4];
  19         int intTex[2];
  20         int intTexStep[2];
  21 } SWspan;
  22 static void simple_textured_triangle( SWvertex * v1)
  23 {
  24         SWvertex *v0;
  25         SWvertex *v2;
  26         typedef struct {
  27                 float dx;
  28                 float dy;
  29                 int fsx;
  30                 int fx0;
  31                 int lines;
  32         } EdgeT;
  33         EdgeT eMaj;
  34         EdgeT eTop;
  35         EdgeT eBot;
  36         float oneOverArea;
  37         SWvertex *vMin;
  38         SWvertex *vMid;
  39         SWvertex *vMax;
  40         int vMin_fx;
  41         int vMin_fy;
  42         int vMid_fx;
  43         int vMid_fy;
  44         int vMax_fx;
  45         int vMax_fy;
  46         SWspan span;
  47          int fy0 = v0->attrib[0][1];
  48          int fy1 = v1->attrib[0][1];
  49          int fy2 = v2->attrib[0][1];
  50         if (fy1 <= fy2) {
  51                 vMin = v0;
  52                 vMax = v1;
  53                 vMin_fy = fy0;
  54         }
  55         vMin_fx = vMin->attrib[0][0];
  56         vMid_fx = (int)
  57               (vMid->attrib[4][0] ?
  58 ((vMid->attrib[4][0] * (float)2048) + 0.5F) :
  59 ((vMid->attrib[4][0] * (float)2048) - 0.5F));
  60         eMaj.dx = (vMax_fx - vMin_fx) * (1.0F / (float)2048);
  61         eMaj.dy = (vMax_fy - vMin_fy) * (1.0F / (float)2048);
  62         eTop.dx = (vMax_fx - vMid_fx) * (1.0F / (float)2048);
  63         eBot.dy = (vMid_fy - vMin_fy) * (1.0F / (float)2048);
  64         float area = eMaj.dx * eBot.dy - eBot.dx * eMaj.dy;
  65         if (IS_INF_OR_NAN(area))
  66                 return;
  67         oneOverArea = 1.0F / area;
  68         eBot.fx0 = vMin_fx;
  69         int scan_from_left_to_right;
  70         void (*PutRowRGB)();
  71         char *texture;
  72         float eMaj_ds = (vMax->attrib[4][0] - vMin->attrib[4][0]);
  73         float eBot_ds;
  74         span.attrStepX[4][0] =
  75             oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds);
  76         span.intTexStep[0] =
  77             (int)
  78               ((span.attrStepX[4][0] >=
  79                 0.0F) ? span.attrStepX[4][0] :
  80 (span.attrStepX[4][0] * (float)2048) - 0.5F);
  81         int subTriangle;
  82         int fxRightEdge = 0;
  83         for (subTriangle = 0; subTriangle <= 1; subTriangle++) {
  84                 EdgeT *eRight;
  85                 int lines;
  86                 if (subTriangle == 0) {
  87                         if (scan_from_left_to_right) {
  88                                 eRight = &eBot;
  89                                 lines = eRight->lines;
  90                         } else {
  91                                 eRight = &eMaj;
  92                         }
  93                 } else {
  94                         if (scan_from_left_to_right) {
  95                                 eRight = &eTop;
  96                         }
  97                         fxRightEdge = eRight->fsx;
  98                 }
  99                 while (lines > 0) {
 100                         span.x = 0;
 101                         if (fxRightEdge <= span.x)
 102                                 span.end = 0;
 103                         else
 104                                 span.end = fxRightEdge - span.x;
 105                         span.intTex[0] = 0;
 106                         if (span.end > 0 && span.y >= 0) {
 107                                 int i;
 108                                 char *rgb;
 109                                 for (i = 0; i < span.end; i++) {
 110                                         rgb[i] = texture[span.intTex[0]];
 111                                         span.intTex[0] += span.intTexStep[0];
 112                                 }
 113                                 PutRowRGB(rgb);
 114                         }
 115                 }
 116         }
 117 }
 118
 119 void *foo()
 120 {
 121         return simple_textured_triangle;
 122 }