Attachment 25653 Details for Bug 20340 – Test program for investigation

Test program for investigation

gl-texture-fragprog.c (text/plain), 5.84 KB, created by Owen Taylor on 2009-05-08 15:55:09 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Owen Taylor

Created: 2009-05-08 15:55:09 UTC

Size: 5.84 KB

patch

obsolete

>/* -*- mode: C; c-basic-offset: 4; indent-tabs-mode: nil; -*- */
>
>/*
> * Compile with:
> *
> * gcc -g -Wall -o gl-texture-fragprog gl-texture-fragprog.c `pkg-config --cflags --libs gl glu` -lglut -lglew
> *
> * This is a program to analyze how a 1x1 checkerboard texture is
> * displayed when it is mapped 1:1 onto screen pixels.
> *
> * Based on:
> * Simple GLUT program to measure triangle strip rendering speed.
> * Brian Paul  February 15, 1997  This file is in the public domain.
> */
>
>#include <stdio.h>
>#include <stdlib.h>
>#include <math.h>
>#include <string.h>
>#include <string.h>
>#include <GL/glew.h>
>#include <GL/glut.h>
>#include <assert.h>
>
>// Size of the quad we display
>#define SIZE 256
>
>// Size of the texture we map
>#define TEXTURE_SIZE 256
>
>static const char *texcoord_prog =
>  "!!ARBfp1.0\n"
>  "PARAM m = {256, 256, 256, 256}; \n"
>  "PARAM m2 = {16., 16., 16., 16.}; \n"
>  "PARAM half = {0.5, 0.5, 0.5, 0.5 }; \n"
>  "PARAM eps = {0.0078125, 0.0078125, 0.0078125, 0.0078125 }; \n"
>  "PARAM one = {1., 1., 1., 1. }; \n"
>  "PARAM zero = {0., 0., 0., 0. }; \n"
>  "TEMP R0, R1, R2, R3, R4; \n"
>
>  // We expect the x/y fractional part of the texture coordinate
>  // to both be 0.5, compute the deviation from that and multiply
>  // by 'm' to scale the deviation to something visibile.
>  "FRC R0, fragment.texcoord; \n"
>  "SUB R0, R0, half; \n"
>  "ABS R0, R0; \n"
>  "MUL R0, R0, m; \n"
>
>  // Compute the ideal texture color for this fragment; this is
>  // (floor(texcoord.x) + floor(texcoord.y)) % 2
>  "FLR R2, fragment.texcoord; \n"
>  "ADD R2.xyzw, R2.xxxx, R2.yyyy; \n"
>  "MUL R2, R2, half; \n"
>  "FRC R2, R2; \n"
>  "SUB R2, R2, half; \n"
>  "CMP R2, R2, zero, one; \n"
>
>  // TEXTURE FETCH VARIANTS
>
>  // Normal texture fetch
>  "TXP R3, fragment.texcoord, texture[0], RECT; \n"
>
>  // Some alternate texture fetches
>
>  // Add eps to the texture coordinates
>  // "ADD R1.xy, fragment.texcoord, eps; \n"
>  // "TXP R3, R1, texture[0], RECT; \n"
>
>  // Force all the coordinates to be exactly 0.5
>  // "FLR R1, fragment.texcoord; \n"
>  //  "ADD R1.xy, R1, half; \n"
>  // "TXP R3, R1, texture[0], RECT; \n"
>
>  // Flip the sign on the error from 1/2
>  // "FLR R1, fragment.texcoord; \n"
>  // "FRC R4, fragment.texcoord; \n"
>  // "SUB R4, one, R4; \n"
>  // "ADD R1.xy, R1, R4; \n"
>  // "TXP R3, R1, texture[0], RECT; \n"
>
>  // Display VARIANTS
>
>  // Just the sampled texture
>  // "MOV result.color, R3; \n"
>
>  // Sampled texture as red, ideal texture as green
>  // "MOV result.color.r, R2.xxxx; \n"
>  // "MOV result.color.g, R3.xxxx; \n"
>
>  // Composite display:
>  //  red: x deviation from 0.5 * 256
>  //  green: y deviation from 0.5 * 256
>  //  value: error in R of the sampled texture * 16
>  "SUB R3, R2, R3; \n"
>  "ABS R3, R3; \n"
>  "MUL R3, R3, m2; \n"
>  "MOV result.color.r, R0.xxxx; \n"
>  "MOV result.color.g, R0.yyyy; \n"
>  "MOV result.color.b, R3.xxxx; \n"
>
>  "END \n";
>
>static void Display( void )
>{
>  glClearColor( 1.0, 1.0, 1.0, 1.0 );
>  glClear( GL_COLOR_BUFFER_BIT );
>
>  glBegin(GL_QUADS);
>  glTexCoord2f(0, 0);
>  glVertex2f(0, 0);
>  glTexCoord2f(SIZE, 0);
>  glVertex2f(SIZE, 0);
>  glTexCoord2f(SIZE, SIZE);
>  glVertex2f(SIZE, SIZE);
>  glTexCoord2f(0, SIZE);
>  glVertex2f(0, SIZE);
>  glEnd();
>  glFinish();
>
>  glutSwapBuffers();
>}
>
>
>static void Reshape( int width, int height )
>{
>  glViewport( 0, 0, width, height );
>  glMatrixMode( GL_PROJECTION );
>  glLoadIdentity();
>  glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
>  glMatrixMode( GL_MODELVIEW );
>  glLoadIdentity();
>}
>
>static void Key( unsigned char key, int x, int y )
>{
>  (void) x;
>  (void) y;
>  switch (key) {
>  case 27:
>    exit(0);
>    break;
>  }
>  glutPostRedisplay();
>}
>
>// Create 1x1 checkerboard
>static void LoadTex()
>{
>  GLubyte *pixels;
>  int x, y;
>  pixels = (GLubyte *) malloc(3*TEXTURE_SIZE*TEXTURE_SIZE);
>  for (y = 0; y < TEXTURE_SIZE; ++y)
>    for (x = 0; x < TEXTURE_SIZE; ++x) {
>      if ((x + y) % 2 == 0) {
>	pixels[(y*TEXTURE_SIZE+x)*3+0] = 0;
>	pixels[(y*TEXTURE_SIZE+x)*3+1] = 0;
>	pixels[(y*TEXTURE_SIZE+x)*3+2] = 0;
>      } else {
>	pixels[(y*TEXTURE_SIZE+x)*3+0] = 255;
>	pixels[(y*TEXTURE_SIZE+x)*3+1] = 255;
>	pixels[(y*TEXTURE_SIZE+x)*3+2] = 255;
>      }
>    }
>  glEnable(GL_TEXTURE_RECTANGLE_ARB);
>  glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGB8, TEXTURE_SIZE, TEXTURE_SIZE, 0, GL_RGB, GL_UNSIGNED_BYTE, pixels);
>  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
>  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
>}
>
>// Borrowed from mesa/progs/tests/arbfptest1.c
>static void load_program(const char *prog, GLuint prognum)
>{
>  int a;
>  GLint errorpos, errno;
>
>  glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, prognum);
>  glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
>		     strlen(prog), (const GLubyte *) prog);
>
>  assert(glIsProgramARB(prognum));
>  errno = glGetError();
>  printf("glGetError = %d\n", errno);
>  if (errno != GL_NO_ERROR)
>    {
>      glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorpos);
>      printf("errorpos: %d\n", errorpos);
>      printf("%s\n", (char *)glGetString(GL_PROGRAM_ERROR_STRING_ARB));
>
>      for (a=-10; a<10; a++)
>	{
>	  if ((errorpos+a < 0) || (errorpos+a >= strlen(prog))) continue;
>	  printf("%c", prog[errorpos+a]);
>	}
>      printf("\n");
>      exit(1);
>    }
>}
>
>// Set up our program as the framgent shader
>static void LoadProg()
>{
>  GLuint progs[1];
>  glGenProgramsARB(1, progs);
>  glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, progs[0]);
>
>  load_program(texcoord_prog, progs[0]);
>  glEnable(GL_FRAGMENT_PROGRAM_ARB);
>}
>
>
>static void Init( int argc, char *argv[] )
>{
>  LoadTex();
>  LoadProg();
>}
>
>
>int main( int argc, char *argv[] )
>{
>
>  glutInit( &argc, argv );
>  glutInitWindowSize( (int) SIZE, (int) SIZE );
>  glutInitWindowPosition( 0, 0 );
>
>  glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
>
>  glutCreateWindow( argv[0] );
>  glewInit();
>
>  Init( argc, argv );
>  Reshape( SIZE, SIZE );
>
>  glutKeyboardFunc( Key );
>  glutDisplayFunc( Display );
>
>  glutMainLoop();
>  return 0;
>}

Actions: View

Attachments on bug 20340: 23344 | 23345 | 25653 | 25655 | 30043

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.