first person camera

include/test.h

@@ -5,6 +5,7 @@ extern "C" {
 #endif
 
   void load();
+  void draw_hud();
   void draw();
   void update(float lx, float ly, float rx, float ry, float tl, float tr,
               int up, int down, int left, int right);

main.lua

@@ -7,6 +7,7 @@ function init()
    ffi.cdef[[
 void load();
 void draw();
+void draw_hud();
 void update(float lx, float ly, float rx, float ry, float tl, float tr,
             int up, int down, int left, int right);
 ]]
@@ -33,6 +34,7 @@ end
 
 local draw = function()
    test.draw()
+   test.draw_hud()
 end
 
 function love.run()

src/font.cpp

@@ -133,20 +133,17 @@ namespace font {
 
     int i = 0;
     while (s[i] != 0) {
-      char c = s[i];
-      if (c <= 0x20 || c > 0x7f)
-        continue;
-
+      char c = s[i++];
+      if (!(c <= 0x20 || c > 0x7f)) {
         XMFLOAT4X4 transform = glyph_transform(font, x, y);
         glUniformMatrix4fv(location.uniform.transform, 1, GL_FALSE, (float *)&transform);
         XMFLOAT2 glyph = glyph_coordinate(font, c);
         glUniform2fv(location.uniform.glyph, 1, (float *)&glyph);
 
         glDrawElements(GL_TRIANGLE_STRIP, 4, GL_UNSIGNED_BYTE, (void *)0);
+      }
 
       x += font.desc->glyph_width;
-
-      i += 1;
     }
   }
 }

src/test.cpp

@@ -241,8 +241,10 @@ extern "C" {
 struct view_state {
   XMVECTOR up;
   XMVECTOR eye;
+  XMVECTOR forward;
   XMVECTOR direction;
   float fov;
+  float pitch;
 };
 
 view_state view_state;
@@ -260,9 +262,11 @@ void load()
 
   view_state.up = XMVectorSet(0.0f, 0.0f, 1.0f, 0.0f);
   view_state.eye = XMVectorSet(0, 0, 0, 1);
-  view_state.direction = XMVectorSet(1, 0, 0, 0);
+  view_state.forward = XMVectorSet(1, 0, 0, 0);
+  view_state.direction = view_state.forward;
+  view_state.pitch = 0.0;
 
-  view_state.fov = 1.0;
+  view_state.fov = 1.5;
 
   //load_texture_shader_storage();
 
@@ -279,18 +283,30 @@ void load()
   ter_8x16 = font::load_font(font::ter_8x16);
 }
 
+float _ry = 0.0;
+
 void update(float lx, float ly, float rx, float ry, float tl, float tr,
             int up, int down, int left, int right)
 {
   //view_state.yaw += rx;
   XMMATRIX mrz = XMMatrixRotationZ(rx * -0.035);
-  XMMATRIX mry = XMMatrixRotationY(ry * -0.035);
-  view_state.direction = XMVector3Transform(view_state.direction, mrz * mry);
 
-  XMVECTOR normal = XMVector3Cross(view_state.direction, view_state.up);
-  view_state.eye += view_state.direction * -ly + normal * lx + view_state.up * (tl - tr);
+  view_state.forward = XMVector3Transform(view_state.forward, mrz);
+  XMVECTOR normal = XMVector3NormalizeEst(XMVector3Cross(view_state.forward, view_state.up));
 
-  view_state.fov += 0.01 * up + -0.01 * down;
+  view_state.pitch += ry * -0.035;
+  if (view_state.pitch > 1.5f) view_state.pitch = 1.5f;
+  if (view_state.pitch < -1.5f) view_state.pitch = -1.5f;
+
+  XMMATRIX mrn = XMMatrixRotationAxis(normal, view_state.pitch);
+  view_state.direction = XMVector3Transform(view_state.forward, mrn);
+
+  view_state.eye += view_state.forward * -ly + normal * lx + view_state.up * (tl - tr);
+
+  float new_fov = view_state.fov + 0.01 * up + -0.01 * down;
+  if (new_fov > 0.00001f) {
+    view_state.fov = new_fov;
+  }
 }
 
 static inline int popcount(int x)
@@ -298,6 +314,29 @@ static inline int popcount(int x)
   return __builtin_popcount(x);
 }
 
+void asdf(char * const buf, char const * const label, char const * const format, float value)
+{
+  const int label_length = strlen(label);
+  memcpy(buf, label, label_length);
+  int len = snprintf(&buf[label_length], 511 - label_length, format, value);
+  buf[label_length + len] = 0;
+}
+
+void draw_hud()
+{
+  char buf[512];
+
+  float y = 10.0f;
+
+  asdf(buf, "fov: ", "%.3f", view_state.fov);
+  font::draw_string(ter_8x16, buf, 10, y);
+  y += ter_8x16.desc->glyph_height;
+
+  asdf(buf, "pitch: ", "%.9f", view_state.pitch);
+  font::draw_string(ter_8x16, buf, 10, y);
+  y += ter_8x16.desc->glyph_height;
+}
+
 void draw()
 {
   XMVECTOR at = XMVectorAdd(view_state.eye, view_state.direction);
@@ -368,6 +407,4 @@ void draw()
       glDrawElementsInstancedBaseInstance(GL_TRIANGLES, element_count, GL_UNSIGNED_BYTE, indices, instance_count, base_instance);
     }
   }
-
-  font::draw_string(ter_8x16, "test", 10, 10);
 }