110 lines
2.3 KiB
C
110 lines
2.3 KiB
C
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include <GL/glew.h>
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#include <GL/glut.h>
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static void Init(void)
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{
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static const char *modulate2D =
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"!!ARBfp1.0\n"
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"MUL result.depth.z, fragment.color.z, {.1}.x; \n"
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"MOV result.color, fragment.color.z; \n"
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"END"
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;
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GLuint modulateProg;
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if (!GLEW_ARB_fragment_program) {
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printf("Error: GL_ARB_fragment_program not supported!\n");
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exit(1);
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}
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printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
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/* Setup the fragment program */
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glGenProgramsARB(1, &modulateProg);
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glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, modulateProg);
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glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
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strlen(modulate2D), (const GLubyte *)modulate2D);
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printf("glGetError = 0x%x\n", (int) glGetError());
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printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
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(char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
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glEnable(GL_FRAGMENT_PROGRAM_ARB);
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glClearColor(.3, .3, .3, 0);
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}
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static void Reshape(int width, int height)
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{
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glViewport(0, 0, (GLint)width, (GLint)height);
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glMatrixMode(GL_PROJECTION);
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glLoadIdentity();
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glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
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glMatrixMode(GL_MODELVIEW);
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}
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static void Key(unsigned char key, int x, int y)
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{
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switch (key) {
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case 27:
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exit(1);
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default:
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break;
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}
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glutPostRedisplay();
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}
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static void Draw(void)
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{
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glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
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glEnable(GL_DEPTH_TEST);
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glBegin(GL_TRIANGLES);
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glColor4f(.8,0,.5,0);
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glVertex3f( 0.9, -0.9, -30.0);
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glVertex3f( 0.9, 0.9, -30.0);
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glVertex3f(-0.9, 0.0, -30.0);
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glColor4f(0,.8,.7,0);
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glVertex3f(-0.9, -0.9, -40.0);
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glColor4f(0,.8,.7,0);
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glVertex3f(-0.9, 0.9, -40.0);
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glColor4f(0,.8,.3,0);
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glVertex3f( 0.9, 0.0, -40.0);
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glEnd();
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glFlush();
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}
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int main(int argc, char **argv)
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{
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glutInit(&argc, argv);
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glutInitWindowPosition(0, 0); glutInitWindowSize( 300, 300);
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glutInitDisplayMode(GLUT_DEPTH | GLUT_RGB | GLUT_SINGLE);
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if (glutCreateWindow("Depth Test") == GL_FALSE) {
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exit(1);
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}
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glewInit();
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Init();
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glutReshapeFunc(Reshape);
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glutKeyboardFunc(Key);
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glutDisplayFunc(Draw);
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glutMainLoop();
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return 0;
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}
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