Start highPoly demo

programs/highPoly.c

@@ -0,0 +1,120 @@
+/*
+  Example program for small3dlib, testing a high-poly offline model.
+
+  author: Miloslav Ciz
+  license: CC0 1.0
+*/
+
+#include <stdio.h>
+#include <math.h>
+#include <time.h>
+
+#define S3L_STRICT_NEAR_CULLING 0
+
+#if TEXTURES
+  #define S3L_PERSPECTIVE_CORRECTION 2
+#else
+  #define S3L_PERSPECTIVE_CORRECTION 0
+#endif
+
+#define S3L_NEAR (S3L_FRACTIONS_PER_UNIT / 5)
+
+#define S3L_Z_BUFFER 1
+
+#define S3L_PIXEL_FUNCTION drawPixel
+
+#define S3L_RESOLUTION_X 800
+#define S3L_RESOLUTION_Y 600
+
+#include "../small3dlib.h"
+
+#include "alligatorModel.h"
+
+S3L_Unit normals[ALLIGATOR_VERTEX_COUNT * 3];
+
+uint8_t frameBuffer[S3L_RESOLUTION_X * S3L_RESOLUTION_Y * 3];
+
+S3L_Scene scene;
+
+S3L_Vec4 teleportPoint;
+
+uint32_t pixels[S3L_RESOLUTION_X * S3L_RESOLUTION_Y];
+
+void clearScreen()
+{
+  memset(frameBuffer,255,S3L_RESOLUTION_X * S3L_RESOLUTION_Y * 3 * sizeof(uint8_t));
+}
+
+void saveImage(char *fileName)
+{
+  printf("saving image file: %s\n",fileName);
+
+  FILE *f = fopen(fileName,"w");
+  
+  fprintf(f,"P3\n%d %d\n255\n",S3L_RESOLUTION_X,S3L_RESOLUTION_Y);
+
+  for (int i = 0; i < S3L_RESOLUTION_X * S3L_RESOLUTION_Y * 3; i += 3)
+    fprintf(f,"%d %d %d\n",frameBuffer[i],frameBuffer[i + 1],frameBuffer[i + 2]);
+
+  fclose(f);
+}
+
+uint32_t previousTriangle = 1000;
+S3L_Vec4 n0, n1, n2, toLight;
+
+void drawPixel(S3L_PixelInfo *p)
+{
+  if (p->triangleID != previousTriangle)
+  {
+    S3L_getIndexedTriangleValues(
+      p->triangleIndex,
+      scene.models[p->modelIndex].triangles,
+      normals,3,&n0,&n1,&n2);
+
+    previousTriangle = p->triangleID;
+  }
+
+  S3L_Vec4 normal;
+
+  normal.x = S3L_interpolateBarycentric(n0.x,n1.x,n2.x,p->barycentric);
+  normal.y = S3L_interpolateBarycentric(n0.y,n1.y,n2.y,p->barycentric);
+  normal.z = S3L_interpolateBarycentric(n0.z,n1.z,n2.z,p->barycentric);
+
+  S3L_normalizeVec3(&normal);
+
+  uint8_t shading = 
+    S3L_clamp((S3L_dotProductVec3(normal,toLight) + S3L_FRACTIONS_PER_UNIT) / 4,0,255);
+
+  int index = (p->y * S3L_RESOLUTION_X + p->x) * 3;
+
+  frameBuffer[index] = shading;
+  frameBuffer[index + 1] = shading; 
+  frameBuffer[index + 2] = shading; 
+}
+
+int main()
+{
+  S3L_setVec4(&toLight,10,10,10,0);
+
+  S3L_normalizeVec3(&toLight);
+
+  alligatorModelInit();
+ 
+  S3L_computeModelNormals(alligatorModel,normals,0);
+
+  S3L_initScene(&alligatorModel,1,&scene);
+
+  scene.camera.transform.translation.z = -8 * S3L_FRACTIONS_PER_UNIT;
+  scene.camera.transform.translation.x = 9 * S3L_FRACTIONS_PER_UNIT;
+  scene.camera.transform.translation.y = 6 * S3L_FRACTIONS_PER_UNIT;
+
+  S3L_lookAt(scene.models[0].transform.translation,&(scene.camera.transform));
+
+  clearScreen();
+  S3L_newFrame();
+  S3L_drawScene(scene);
+
+  saveImage("allligator.ppm");
+
+  return 0;
+}

programs/hqOffline.c

@@ -140,7 +140,6 @@ void sampleTexture(uint8_t *texture, int w, int h, float x, float y, uint8_t col
   color[0] = interpolate(interpolate(c0[0],c1[0],xFract),interpolate(c2[0],c3[0],xFract),yFract);
   color[1] = interpolate(interpolate(c0[1],c1[1],xFract),interpolate(c2[1],c3[1],xFract),yFract);
   color[2] = interpolate(interpolate(c0[2],c1[2],xFract),interpolate(c2[2],c3[2],xFract),yFract);
-
 }
 
 void drawPixel(S3L_PixelInfo *p)

small3dlib.h

@@ -282,6 +282,13 @@ typedef uint16_t S3L_Index;
 #define S3L_NEAR 1 // Can't be <= 0.
 #endif
 
+#ifndef S3L_NORMAL_COMPUTE_MAXIMUM_AVERAGE
+  /** Affects the S3L_computeModelNormals function. See its description for
+  details. */
+
+  #define S3L_NORMAL_COMPUTE_MAXIMUM_AVERAGE 6
+#endif
+
 #ifndef S3L_FAST_LERP_QUALITY
   /** Quality (scaling) of SOME (stepped) linear interpolations. 0 will most
   likely be a tiny bit faster, but artifacts can occur for bigger tris, while
@@ -570,7 +577,12 @@ void S3L_getIndexedTriangleValues(
   sufficient size preallocated! The size is: number of model vertices * 3 *
   sizeof(S3L_Unit). Note that for advanced allowing sharp edges it is not
   sufficient to have per-vertex normals, but must be per-triangle. This
-  function doesn't support this. */
+  function doesn't support this. 
+
+  The function computes a normal for each vertex by averaging normals of
+  the triangles containing the vertex. The maximum number of these triangle
+  normals that will be averaged is set with
+  S3L_NORMAL_COMPUTE_MAXIMUM_AVERAGE. */
 void S3L_computeModelNormals(S3L_Model3D model, S3L_Unit *dst,
   int8_t transformNormals);
 
@@ -1019,16 +1031,14 @@ void S3L_computeModelNormals(S3L_Model3D model, S3L_Unit *dst,
 
   n.w = 0;
 
-  #define MAX_NORMALS 6
-
-  S3L_Vec4 ns[MAX_NORMALS];
+  S3L_Vec4 ns[S3L_NORMAL_COMPUTE_MAXIMUM_AVERAGE];
   S3L_Index normalCount;
 
-  for (S3L_Index i = 0; i < model.vertexCount; ++i)
+  for (uint32_t i = 0; i < model.vertexCount; ++i)
   {
     normalCount = 0;
 
-    for (S3L_Index j = 0; j < model.triangleCount * 3; j += 3)
+    for (uint32_t j = 0; j < model.triangleCount * 3; j += 3)
     {
       if (
         (model.triangles[j] == i) ||
@@ -1056,7 +1066,7 @@ void S3L_computeModelNormals(S3L_Model3D model, S3L_Unit *dst,
 
         normalCount++;
 
-        if (normalCount >= MAX_NORMALS)
+        if (normalCount >= S3L_NORMAL_COMPUTE_MAXIMUM_AVERAGE)
           break;
       }
     }
@@ -1095,8 +1105,6 @@ void S3L_computeModelNormals(S3L_Model3D model, S3L_Unit *dst,
     vPos++;
   }
     
-  #undef MAX_NORMALS
-    
   S3L_Mat4 m;
 
   S3L_makeWorldMatrix(model.transform,&m);
@@ -1440,6 +1448,16 @@ S3L_Unit S3L_vec2Length(S3L_Vec4 v)
 
 void S3L_normalizeVec3(S3L_Vec4 *v)
 {
+  #define SCALE 16
+
+  v->x *= SCALE;
+  v->y *= SCALE;
+  v->z *= SCALE;
+  
+  // ^ This pre-scale prevents inaccuracy with very small vectors ([1,1,1]).
+
+  #undef SCALE
+
   S3L_Unit l = S3L_vec3Length(*v);
 
   if (l == 0)

todo.txt

@@ -87,6 +87,8 @@ features:
 
 bugs:
 
+- obj tools still crosses the 80 column alignment limit (alligator model)
+
 repeated:
 
 - valgrind (and similar) checks