fix Windows XP build

.gitignore

@@ -6,3 +6,4 @@
 *.blend1
 *.zip
 main
+*.exe

Makefile

@@ -11,8 +11,8 @@ MAKEFILE_PATH := $(patsubst %/,%,$(dir $(abspath $(firstword $(MAKEFILE_LIST))))
 
 DEBUG = -g
 
-CSTD += -std=gnu23
-CXXSTD += -std=gnu++23
+CSTD += -std=gnu11
+CXXSTD += -std=gnu++14
 
 CFLAGS += -Wall -Werror -Wfatal-errors
 CFLAGS += -Wno-error=unused-function
@@ -20,9 +20,9 @@ CFLAGS += -Wno-error=unused-variable
 CFLAGS += -I$(MAKEFILE_PATH)/include
 CFLAGS += -I$(dir $(GLFW))../include
 CXXFLAGS += -fno-exceptions
-LDFLAGS += -nostdlib++ -lm -Wl,-z noexecstack
+LDFLAGS += -lm -static-libgcc
 ifeq ($(shell uname),Linux)
-LDFLAGS += -static-libgcc
+LDFLAGS += -nostdlib++
 endif
 ifeq ($(OS),Windows_NT)
 LDFLAGS += -Wl,--subsystem,windows -mwindows

include/math/transform.hpp

@@ -41,8 +41,8 @@ inline constexpr mat<4, 4, T> rotate_x(T t)
 {
   return {
     1,      0,       0, 0,
-    0, cos(t), -sin(t), 0,
-    0, sin(t),  cos(t), 0,
+    0, cosf(t), -sinf(t), 0,
+    0, sinf(t),  cosf(t), 0,
     0,      0,       0, 1
   };
 }
@@ -51,9 +51,9 @@ template <typename T>
 inline constexpr mat<4, 4, T> rotate_y(T t)
 {
   return {
-    cos(t), 0, sin(t), 0,
+    cosf(t), 0, sinf(t), 0,
          0, 1,      0, 0,
-   -sin(t), 0, cos(t), 0,
+   -sinf(t), 0, cosf(t), 0,
          0, 0,      0, 1
   };
 }
@@ -62,8 +62,8 @@ template <typename T>
 inline constexpr mat<4, 4, T> rotate_z(T t)
 {
   return {
-    cos(t), -sin(t), 0, 0,
-    sin(t),  cos(t), 0, 0,
+    cosf(t), -sinf(t), 0, 0,
+    sinf(t),  cosf(t), 0, 0,
          0,       0, 1, 0,
          0,       0, 0, 1
   };
@@ -149,7 +149,7 @@ template <typename T>
 inline constexpr T inverse_length(vec<3, T> v)
 {
   float f = dot(v, v);
-  return 1.0f / sqrt<T>(f);
+  return 1.0f / sqrtf(f);
 }
 
 template <typename T>

src/main.c

@@ -2,6 +2,7 @@
 #include <unistd.h>
 #include <math.h>
 #include <assert.h>
+#include <stdbool.h>
 
 #include "glad/gl.h"
 
@@ -81,8 +82,8 @@ int main()
 #endif
   glfwInit();
   glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_API);
-  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
+  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
+  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);
   glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_ANY_PROFILE);
 
   GLFWwindow* window = glfwCreateWindow(vp_width, vp_height, "new", NULL, NULL);
@@ -106,6 +107,11 @@ int main()
             GLAD_VERSION_MAJOR(version), GLAD_VERSION_MINOR(version));
     return -1;
   }
+  printf("%d %d %d\n",
+	 GLAD_GL_ARB_framebuffer_object,
+	 GLAD_GL_ARB_texture_float,
+	 GLAD_GL_ARB_vertex_array_object);
+  fflush(stdout);
 
   //////////////////////////////////////////////////////////////////////
   // meshes
@@ -173,6 +179,8 @@ int main()
   const double first_frame = glfwGetTime();
   double last_frame = first_frame;
 
+  fflush(stderr);
+
   while (!glfwWindowShouldClose(window)) {
     if(glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
       glfwSetWindowShouldClose(window, true);

src/shader/scene.fs.glsl

@@ -1,5 +1,7 @@
 #version 130
 
+precision highp float;
+
 uniform sampler2D texture0;
 
 in vec2 f_texture;