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Diffstat (limited to 'progs/glsl/multitex.c')
-rw-r--r-- | progs/glsl/multitex.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/progs/glsl/multitex.c b/progs/glsl/multitex.c new file mode 100644 index 0000000000..5574ed4139 --- /dev/null +++ b/progs/glsl/multitex.c @@ -0,0 +1,285 @@ +/** + * Test multi-texturing with GL shading language. + * + * Copyright (C) 2008 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + + + +#include <assert.h> +#include <math.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "GL/glut.h" +#include "readtex.h" +#include "extfuncs.h" +#include "shaderutil.h" + +static const char *Demo = "multitex"; + +static const char *VertFile = "multitex.vert.txt"; +static const char *FragFile = "multitex.frag.txt"; + +static const char *TexFiles[2] = + { + "../images/tile.rgb", + "../images/tree2.rgba" + }; + + +static GLuint Program; + +static GLfloat Xrot = -90.0, Yrot = .0, Zrot = 0.0; +static GLfloat EyeDist = 10; +static GLboolean Anim = GL_TRUE; + + +/* value[0] = tex unit */ +static struct uniform_info Uniforms[] = { + { "tex1", 1, GL_INT, { 0, 0, 0, 0 }, -1 }, + { "tex2", 1, GL_INT, { 1, 0, 0, 0 }, -1 }, + END_OF_UNIFORMS +}; + + +static void +DrawPolygon(GLfloat size) +{ + glPushMatrix(); + glRotatef(90, 1, 0, 0); + glNormal3f(0, 0, 1); + glBegin(GL_POLYGON); + + glMultiTexCoord2f(GL_TEXTURE0, 0, 0); + glMultiTexCoord2f(GL_TEXTURE1, 0, 0); + glVertex2f(-size, -size); + + glMultiTexCoord2f(GL_TEXTURE0, 2, 0); + glMultiTexCoord2f(GL_TEXTURE1, 1, 0); + glVertex2f( size, -size); + + glMultiTexCoord2f(GL_TEXTURE0, 2, 2); + glMultiTexCoord2f(GL_TEXTURE1, 1, 1); + glVertex2f( size, size); + + glMultiTexCoord2f(GL_TEXTURE0, 0, 2); + glMultiTexCoord2f(GL_TEXTURE1, 0, 1); + glVertex2f(-size, size); + + glEnd(); + glPopMatrix(); +} + + +static void +draw(void) +{ + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + glPushMatrix(); /* modelview matrix */ + glTranslatef(0.0, 0.0, -EyeDist); + glRotatef(Zrot, 0, 0, 1); + glRotatef(Yrot, 0, 1, 0); + glRotatef(Xrot, 1, 0, 0); + + DrawPolygon(3.0); + + glPopMatrix(); + + glutSwapBuffers(); +} + + +static void +idle(void) +{ + GLfloat t = 0.05 * glutGet(GLUT_ELAPSED_TIME); + Yrot = t; + glutPostRedisplay(); +} + + +static void +key(unsigned char k, int x, int y) +{ + (void) x; + (void) y; + switch (k) { + case ' ': + case 'a': + Anim = !Anim; + if (Anim) + glutIdleFunc(idle); + else + glutIdleFunc(NULL); + break; + case 'z': + EyeDist -= 0.5; + if (EyeDist < 3.0) + EyeDist = 3.0; + break; + case 'Z': + EyeDist += 0.5; + if (EyeDist > 90.0) + EyeDist = 90; + break; + case 27: + exit(0); + } + glutPostRedisplay(); +} + + +static void +specialkey(int key, int x, int y) +{ + GLfloat step = 2.0; + (void) x; + (void) y; + switch (key) { + case GLUT_KEY_UP: + Xrot += step; + break; + case GLUT_KEY_DOWN: + Xrot -= step; + break; + case GLUT_KEY_LEFT: + Yrot -= step; + break; + case GLUT_KEY_RIGHT: + Yrot += step; + break; + } + glutPostRedisplay(); +} + + +/* new window size or exposure */ +static void +Reshape(int width, int height) +{ + GLfloat ar = (float) width / (float) height; + glViewport(0, 0, (GLint)width, (GLint)height); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glFrustum(-2.0*ar, 2.0*ar, -2.0, 2.0, 4.0, 100.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); +} + + +static void +InitTextures(void) +{ + GLenum filter = GL_LINEAR; + int i; + + for (i = 0; i < 2; i++) { + GLint imgWidth, imgHeight; + GLenum imgFormat; + GLubyte *image = NULL; + + image = LoadRGBImage(TexFiles[i], &imgWidth, &imgHeight, &imgFormat); + if (!image) { + printf("Couldn't read %s\n", TexFiles[i]); + exit(0); + } + + glActiveTexture(GL_TEXTURE0 + i); + glBindTexture(GL_TEXTURE_2D, 42 + i); + gluBuild2DMipmaps(GL_TEXTURE_2D, 4, imgWidth, imgHeight, + imgFormat, GL_UNSIGNED_BYTE, image); + free(image); + + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter); + } +} + + +static GLuint +CreateProgram(const char *vertProgFile, const char *fragProgFile, + struct uniform_info *uniforms) +{ + GLuint fragShader, vertShader, program; + + vertShader = CompileShaderFile(GL_VERTEX_SHADER, vertProgFile); + fragShader = CompileShaderFile(GL_FRAGMENT_SHADER, fragProgFile); + assert(vertShader); + program = LinkShaders(vertShader, fragShader); + + glUseProgram_func(program); + + InitUniforms(program, uniforms); + + return program; +} + + +static void +InitPrograms(void) +{ + Program = CreateProgram(VertFile, FragFile, Uniforms); +} + + +static void +InitGL(void) +{ + const char *version = (const char *) glGetString(GL_VERSION); + + if (version[0] != '2' || version[1] != '.') { + printf("Warning: this program expects OpenGL 2.0\n"); + /*exit(1);*/ + } + printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER)); + + GetExtensionFuncs(); + + InitTextures(); + InitPrograms(); + + glEnable(GL_DEPTH_TEST); + + glClearColor(.6, .6, .9, 0); + glColor3f(1.0, 1.0, 1.0); +} + + +int +main(int argc, char *argv[]) +{ + glutInit(&argc, argv); + glutInitWindowSize(500, 400); + glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE); + glutCreateWindow(Demo); + glutReshapeFunc(Reshape); + glutKeyboardFunc(key); + glutSpecialFunc(specialkey); + glutDisplayFunc(draw); + if (Anim) + glutIdleFunc(idle); + InitGL(); + glutMainLoop(); + return 0; +} |