Refactor, GLFW->SDL

[vg.git] / vg_tex.h

diff --git a/vg_tex.h b/vg_tex.h
new file mode 100644 (file)
index 0000000..5c7c7f6
--- /dev/null
+++ b/vg_tex.h
@@ -0,0 +1,198 @@
+/* Copyright (C) 2021-2022 Harry Godden (hgn) - All Rights Reserved */
+#ifndef VG_TEX_H
+#define VG_TEX_H
+
+#include "vg/vg.h"
+#include "vg/vg_log.h"
+
+#define VG_TEXTURE_NO_MIP      0x1
+#define VG_TEXTURE_REPEAT      0x2
+#define VG_TEXTURE_CLAMP       0x4
+#define VG_TEXTURE_NEAREST     0x8
+#define VG_TEXTURE_ALLOCATED_INTERNAL 0x10
+
+VG_STATIC void *vg_qoi_malloc( size_t size )
+{
+   return vg_linear_alloc( vg_mem.scratch, size );
+}
+
+VG_STATIC void vg_qoi_free( void *ptr )
+{
+   
+}
+
+#define QOI_IMPLEMENTATION
+#define QOI_NO_STDIO
+#define QOI_MALLOC(sz) vg_qoi_malloc( sz )
+#define QOI_FREE(p) vg_qoi_free( p )
+
+#include "submodules/qoi/qoi.h"
+
+struct vg_tex2d
+{
+       const char *path;
+       u32 flags;
+       GLuint name;
+};
+
+struct vg_sprite
+{
+       v4f uv_xywh;
+};
+
+VG_STATIC void vg_tex2d_bind( vg_tex2d *tex, u32 id )
+{
+   if( !(tex->flags & VG_TEXTURE_ALLOCATED_INTERNAL) )
+   {
+      vg_error( "Tried to use '%s' while unloaded!\n", tex->path );
+      return;
+   }
+
+       glActiveTexture( GL_TEXTURE0 + id );
+       glBindTexture( GL_TEXTURE_2D, tex->name );
+}
+
+static inline void vg_tex2d_mipmap(void) 
+{ 
+       glGenerateMipmap( GL_TEXTURE_2D );
+}
+
+static inline void vg_tex2d_linear(void)
+{
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
+}
+
+static inline void vg_tex2d_nearest(void)
+{
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+}
+
+static inline void vg_tex2d_linear_mipmap(void)
+{
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, 
+         GL_LINEAR_MIPMAP_LINEAR );
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
+}
+
+static inline void vg_tex2d_repeat(void)
+{
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );
+}
+
+static inline void vg_tex2d_clamp(void)
+{
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
+       glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
+}
+
+VG_STATIC GLuint vg_tex2d_new(void)
+{
+       GLuint texture_name;
+       glGenTextures( 1, &texture_name );
+       glBindTexture( GL_TEXTURE_2D, texture_name );
+
+   return texture_name;
+}
+
+VG_STATIC void vg_tex2d_set_error(void)
+{
+   u32 tex_err[4] =
+   {
+      0xffff00ff,
+      0xff000000,
+      0xff000000,
+      0xffff00ff
+   };
+
+   glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 2, 2, 
+                  0, GL_RGBA, GL_UNSIGNED_BYTE, tex_err );
+}
+
+VG_STATIC void vg_tex2d_qoi( void *mem, u32 size, const char *name )
+{
+   qoi_desc info;
+   u8 *tex_buffer = qoi_decode( mem, size, &info, 4 );
+
+   if( tex_buffer )
+   {
+      vg_info( "Texture decoded: [%u %u] %s\n", 
+                                    info.width, info.height, name );
+
+      glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, info.width, info.height, 
+                    0, GL_RGBA, GL_UNSIGNED_BYTE, tex_buffer );
+
+      QOI_FREE(tex_buffer);
+   }
+   else
+   {
+      vg_error( "File size: %u\n", size );
+      vg_tex2d_set_error();
+   }
+}
+
+VG_STATIC GLuint vg_tex2d_rgba( const char *path )
+{
+   GLuint texture_name = vg_tex2d_new();
+
+   vg_linear_clear( vg_mem.scratch );
+   u32 size;
+   void *file = vg_file_read( vg_mem.scratch, path, &size );
+
+   if( file )
+   {
+      vg_tex2d_qoi( file, size, path );
+   }
+   else
+   {
+               vg_error( "Loading texture failed (%s)\n", path );
+      vg_tex2d_set_error();
+   }
+
+       return texture_name;
+}
+
+VG_STATIC void vg_tex2d_init( vg_tex2d *textures[], int num )
+{
+       for( int i=0; i<num; i ++ )
+       {
+               vg_tex2d *tex = textures[i];
+               tex->name = vg_tex2d_rgba( tex->path );
+               if( !(tex->flags & VG_TEXTURE_NO_MIP) )
+                       vg_tex2d_mipmap();
+
+               if( tex->flags & VG_TEXTURE_NEAREST )
+               {
+                       if( tex->flags & VG_TEXTURE_NO_MIP )
+                               vg_error( "Invalid texture settings\n" );
+                       else
+                               vg_tex2d_nearest();
+               }
+               else
+               {
+                       if( tex->flags & VG_TEXTURE_NO_MIP )
+                               vg_tex2d_linear();
+                       else
+                               vg_tex2d_linear_mipmap();
+               }
+               
+               if( tex->flags & VG_TEXTURE_CLAMP )
+                       vg_tex2d_clamp();
+               else
+                       vg_tex2d_repeat();
+
+      tex->flags |= VG_TEXTURE_ALLOCATED_INTERNAL;
+       }
+}
+
+VG_STATIC void vg_tex2d_free( vg_tex2d *textures[], int num )
+{
+       for( int i = 0; i < num; i ++ )
+       {
+               glDeleteTextures( 1, &textures[i]->name );
+       }
+}
+
+#endif /* VG_TEX_H */