add fps uniform

src/forge.c

@@ -1,4 +1,5 @@
 #include <linmath.h>
+#include <math.h>
 #include <stdbool.h>
 #include <stdlib.h>
 
@@ -25,8 +26,8 @@ static void key_callback(Window *window, int key,
   }
 }
 
-void compute_fps(Window *window, Timer *timer) {
-  double fps;
+int compute_fps(Window *window, Timer *timer) {
+  static double fps;
   char title[100];
 
   if (inc_timer(timer)) {
@@ -34,6 +35,8 @@ void compute_fps(Window *window, Timer *timer) {
     sprintf(title, PACKAGE " " VERSION " - %.0ffps", fps);
     update_window_title(window, title);
   }
+
+  return (int)round(fps);
 }
 
 void hot_reload(ShaderProgram program, File *common_shader_code,
@@ -59,14 +62,14 @@ void loop(Window *window, ShaderProgram program, bool hr,
           File *common_shader_code, File *fragment_shaders, Timer *timer) {
   Context context;
 
-  compute_fps(window, timer);
-
   if (hr) {
     hot_reload(program, common_shader_code, fragment_shaders);
   }
 
   context = get_window_context(window);
 
+  context.fps = compute_fps(window, timer);
+
   apply_program(program, context);
 
   refresh_window(window);
@@ -132,7 +135,7 @@ void forge_run(Parameters params) {
     exit(EXIT_FAILURE);
   }
 
-  timer = create_timer(60);
+  timer = create_timer(30);
 
   while (!window_should_close(window)) {
     loop(window, program, params.hot_reload, &common_shader_code,

src/shaders.c

@@ -142,6 +142,8 @@ void init_single_program(ShaderProgram *program, int i, bool output) {
         glGetUniformLocation(program->programs[i], "iTime");
     program->itempo_locations[i] =
         glGetUniformLocation(program->programs[i], "iTempo");
+    program->ifps_locations[i] =
+        glGetUniformLocation(program->programs[i], "iFPS");
     program->ires_locations[i] =
         glGetUniformLocation(program->programs[i], "iResolution");
   }
@@ -245,7 +247,9 @@ void apply_program(ShaderProgram program, Context context) {
 
       // set fragment uniforms
       glUniform1f(program.itime_locations[i], (const GLfloat)context.time);
-      glUniform1f(program.itempo_locations[i], (const GLfloat)120); // TODO TMP
+      glUniform1f(program.itempo_locations[i],
+                  (const GLfloat)120.0f); // TODO TMP
+      glUniform1i(program.ifps_locations[i], (const GLint)context.fps);
       glUniform2fv(program.ires_locations[i], 1, (const GLfloat *)&resolution);
     }
 

src/types.h

@@ -42,6 +42,7 @@ typedef struct ShaderProgram {
 
   GLuint itime_locations[FRAG_COUNT];
   GLuint itempo_locations[FRAG_COUNT];
+  GLuint ifps_locations[FRAG_COUNT];
   GLuint ires_locations[FRAG_COUNT];
   GLuint frames_locations[FRAG_COUNT + 1][TEX_COUNT];
   GLuint vpos_locations[FRAG_COUNT + 1];
@@ -61,6 +62,7 @@ typedef struct Context {
   int width;
   int height;
   double time;
+  int fps;
 } Context;
 
 typedef struct Timer {