test.pl stop using GLU

Author: mohawk2

Changes

@@ -1,3 +1,5 @@
+- add glpErrorString
+
 0.7006 2025-04-14
 - incorporate Acme::MITHALDU::BleedingOpenGL changes - thanks @wchristian
 - add glGenVertexArrays_p, glBindVertexArray, glDeleteVertexArrays

MANIFEST

@@ -37,6 +37,7 @@ FreeGLUT/freeglut.lib
 FreeGLUT/README.txt
 genvars.pl
 gl_const.h
+gl_errors.h
 gl_util.c
 gl_util.h
 glext_consts.h

gl_errors.h

@@ -0,0 +1,32 @@
+/*
+#define GL_NO_ERROR                      0
+#define GL_INVALID_ENUM                  0x0500
+#define GL_INVALID_VALUE                 0x0501
+#define GL_INVALID_OPERATION             0x0502
+#define GL_STACK_OVERFLOW                0x0503
+#define GL_STACK_UNDERFLOW               0x0504
+#define GL_OUT_OF_MEMORY                 0x0505
+#define GL_INVALID_FRAMEBUFFER_OPERATION 0x0506
+#define GL_CONTEXT_LOST                  0x0507
+*/
+
+const char* const gl_error_symbol_strings[] = {
+    "GL_NO_ERROR",
+    "GL_INVALID_ENUM",
+    "GL_INVALID_VALUE",
+    "GL_INVALID_OPERATION",
+    "GL_STACK_OVERFLOW",
+    "GL_STACK_UNDERFLOW",
+    "GL_OUT_OF_MEMORY",
+    "GL_INVALID_FRAMEBUFFER_OPERATION",
+    "GL_CONTEXT_LOST",
+};
+
+int is_gl_error(int rval) {
+    if (!(rval & 0x0507)) return 0;
+    return (rval & 0x07) + 1;
+}
+
+const char* gl_error_string(int err) {
+    return gl_error_symbol_strings[is_gl_error(err)];
+}

lib/OpenGL.pm

@@ -1209,6 +1209,7 @@ our @gl_func = (@gl_func_common, qw(
    glWindowPos4dMESA
    glWindowPos4iMESA
    glpCheckExtension
+   glpErrorString
    glpFullScreen
    glpHasGLUT
    glpRestoreScreen

lib/OpenGL/V1.xs

@@ -8,6 +8,7 @@
 #include <stdio.h>
 
 #include "pgopogl.h"
+#include "gl_errors.h"
 
 #ifdef HAVE_GL
 #include "gl_util.h"
@@ -10322,4 +10323,12 @@ glBlendColorEXT(red, green, blue, alpha)
 
 #endif
 
+const char *
+glpErrorString(err)
+  int err
+CODE:
+  RETVAL = gl_error_string(err);
+OUTPUT:
+  RETVAL
+
 #endif /* HAVE_GL */

test.pl

@@ -7,7 +7,7 @@
 use OpenGL qw/
   :glconstants
   glpHasGLUT glpCheckExtension glpFullScreen glpRestoreScreen
-  glGetString glGetError
+  glGetString glGetError glpErrorString
   glGenTextures_p glBindTexture glTexParameteri glTexImage2D_c glTexEnvf
     glDeleteTextures_p
   glGenerateMipmapEXT
@@ -25,7 +25,7 @@
     glTranslatef glRotatef
     glColor3f glColor4f
     glPushMatrix glPopMatrix glPushAttrib glPopAttrib
-    glOrtho
+    glOrtho glFrustum
   glRasterPos2i glRasterPos2f
   glPixelZoom glReadPixels_c glDrawPixels_c
   glGetDoublev_c glGetIntegerv_c
@@ -34,10 +34,6 @@
 use OpenGL::GLUT qw/
   :constants :functions
 /;
-use OpenGL::GLU qw/
-  gluBuild2DMipmaps_c gluErrorString
-  gluOrtho2D gluProject_p gluUnProject_p gluPerspective
-/;
 use OpenGL::Config;     # for build information
 
 eval 'use OpenGL::Image 1.03';  # Need to use OpenGL::Image 1.03 or higher!
@@ -588,12 +584,16 @@ sub ourBuildTextures
     GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
     GL_NEAREST_MIPMAP_LINEAR);
-  # The GLU library helps us build MipMaps for our texture.
-  if (($gluerr = gluBuild2DMipmaps_c(GL_TEXTURE_2D, $Tex_Type,
-    $Tex_Width, $Tex_Height, $Tex_Format, $Tex_Size,
-    $Tex_Pixels->ptr())))
-  {
-    die sprintf "GLULib%s\n", gluErrorString($gluerr);
+  glTexImage2D_c(GL_TEXTURE_2D, 0, $Tex_Type,
+    $Tex_Width, $Tex_Height,
+    0, $Tex_Format, $Tex_Size, $Tex_Pixels->ptr);
+  glGenerateMipmapEXT(GL_TEXTURE_2D);
+  if ($^O ne 'MSWin32') {
+    my $errors = '';
+    while((my $err = glGetError()) != 0) {
+      $errors .= "glError: " . glpErrorString($err) . "\n";
+    }
+    die $errors if $errors;
   }
 
   # Benchmarks for Image Loading
@@ -679,7 +679,7 @@ sub ourBuildTextures
 
     # Test status
     my $stat = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
-    die "FBO Status error: " . gluErrorString(glGetError()) if !$stat;
+    die "FBO Status error: " . glpGetError(glGetError()) if !$stat;
     die sprintf "FBO Status: %04X", $stat if $stat != GL_FRAMEBUFFER_COMPLETE_EXT;
   }
 
@@ -1065,7 +1065,7 @@ sub Capture
   glMatrixMode( GL_PROJECTION );
   glPushMatrix();
   glLoadIdentity();
-  eval { gluOrtho2D( 0, $w, 0, $h ); 1 } or $er++ or warn "Catched: $@";
+  eval { glOrtho( 0, $w, 0, $h, -1, 1 ); 1 } or $er++ or warn "Catched: $@";
   glMatrixMode( GL_MODELVIEW );
   glPushMatrix();
   glLoadIdentity();
@@ -1408,16 +1408,6 @@ sub cbMouseClick
   if ($state == GLUT_UP)
   {
     my ($model, $projection, $viewport) = dumpMatrices();
-    my @point = gluUnProject_p($x,$y,0,	# Cursor point
-      @$model,				# Model Matrix
-      @$projection,			# Projection Matrix
-      @$viewport);			# Viewport
-    print "Model point: $point[0], $point[1], $point[2]\n";
-#      @point = gluProject_p(@point,	# Model point
-#        @model,				# Model Matrix
-#        @projection,			# Projection Matrix
-#        @viewport);			# Viewport
-#      print "Window point: $point[0], $point[1], $point[2]\n";
     print "\n";
   }
 
@@ -1456,26 +1446,26 @@ sub GetKeyModifier
 # ------
 # Callback routine executed whenever our window is resized.  Lets us
 # request the newly appropriate perspective projection matrix for
-# our needs.  Try removing the gluPerspective() call to see what happens.
-
-sub cbResizeScene
-{
+# our needs.  Try removing the glFrustum() call to see what happens.
+
+use constant PI => 3.1415926535897932384626433832795;
+use constant FOVY => 45.0;
+use constant ANGLE => FOVY / 360 * PI;
+use constant TAN => sin(ANGLE)/cos(ANGLE);
+use constant { zNEAR => 0.1, zFAR => 100.0 };
+use constant fH => TAN * zNEAR;
+sub cbResizeScene {
   my($Width, $Height) = @_;
-
   # Let's not core dump, no matter what.
   $Height = 1 if ($Height == 0);
-
   glViewport(0, 0, $Width, $Height);
-
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
-  gluPerspective(45.0,$Width/$Height,0.1,100.0);
-
+  my $fW = fH * $Width/$Height;
+  glFrustum(-$fW, $fW, -fH, fH, zNEAR, zFAR);
   glMatrixMode(GL_MODELVIEW);
-
   $Window_Width  = $Width;
   $Window_Height = $Height;
-
   $idleTime = $hasHires ? gettimeofday() : time();
 }
 
@@ -1651,7 +1641,7 @@ sub quit {
 if ($^O ne 'MSWin32') {
   my $errors = '';
   while((my $err = glGetError()) != 0) {
-    $errors .= "glError: " . gluErrorString($err) . "\n";
+    $errors .= "glError: " . glpErrorString($err) . "\n";
   }
   die $errors if $errors;
 }