Attachment 59958 Details for Bug 48678 – Program that triggers the problem.

Program that triggers the problem.

ball.c (text/x-csrc), 2.66 KB, created by Lucas on 2012-04-13 23:09:38 UTC

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Description:

Filename:

MIME Type:

Creator: Lucas

Created: 2012-04-13 23:09:38 UTC

Size: 2.66 KB

patch

obsolete

>#include <stdlib.h>
>#include <stdio.h>
>#include <math.h>
>
>#include <GL/glew.h>
>#include <GL/glut.h>
>
>// Creates a round texture, taken from here:
>// https://www.gitorious.org/glome/glome/blobs/3412a08f3d38b1602e9a82e4baaba0bdf31ed802/src/common/textures.cpp
>GLuint create_spherical_texture(int size)
>{
>	typedef struct {
>		unsigned char l;
>		unsigned char a;
>	} elem;
>	GLuint tex;
>	int i, j;
>
>	elem* buffer = (elem *) malloc(size * size * sizeof(elem));
>	float r = (float)size / 2.0;
>
>	for(i = 0; i < size; ++i)
>	{
>		for(j = 0; j < size; ++j)
>		{
>			float d = hypotf(i - r, j - r);
>			buffer[(i * size) + j].l = 255u;
>			buffer[(i * size) + j].a = d > r ? 0u : (unsigned char)nearbyint(sqrtf(r*r - d*d) / r * 255.0);
>		}
>	}
>
>	glGenTextures(1, &tex);
>	glBindTexture(GL_TEXTURE_2D, tex);
>	glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE_ALPHA, size, size, 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, (GLvoid*)buffer);
>	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
>
>	free(buffer);
>
>	return tex;
>}
>
>void initialize()
>{
>  glewInit();
>
>  if(! GLEW_VERSION_2_0) {
>    fputs("Error: Needs at least OpenGL 2.0\n", stderr);
>    exit(1);
>  }
>
>  const char *vcode =
>    "#version 120\n"
>    "attribute vec4 position;\n"
>    "void main()\n"
>    "{\n"
>    "  gl_Position = position;\n"
>    "  gl_PointSize = 128.0;\n"
>    "}\n";
>
>  const char *fcode =
>    "#version 120\n"
>    "uniform sampler2D tex;\n"
>    "void main()\n"
>    "{\n"
>    "  gl_FragColor = vec4(gl_PointCoord, 1.0, 1.0)"
>    "    * texture2D(tex, gl_PointCoord);\n"
>    "}\n";
>
>  GLint tex_sampler;
>  GLuint texture;
>  GLuint prog = glCreateProgram();
>  GLuint vshader = glCreateShader(GL_VERTEX_SHADER);
>  GLuint fshader = glCreateShader(GL_FRAGMENT_SHADER);
>
>  glShaderSource(vshader, 1, &vcode, NULL);
>  glShaderSource(fshader, 1, &fcode, NULL);
>
>  glCompileShader(vshader);
>  glCompileShader(fshader);
>
>  glAttachShader(prog, vshader);
>  glAttachShader(prog, fshader);
>
>  glBindAttribLocation(prog, 0, "position");
>  glLinkProgram(prog);
>
>  glUseProgram(prog);
>  glUniform1i(glGetUniformLocation(prog, "tex"), 0);
>
>  glEnable(GL_TEXTURE_2D);
>  glActiveTexture(GL_TEXTURE0);
>  create_spherical_texture(128);
>
>  glDisable(GL_DEPTH_TEST);
>  glEnable(GL_PROGRAM_POINT_SIZE);
>  glEnable(GL_POINT_SPRITE);
>  glEnable(GL_BLEND);
>  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
>}
>
>void draw()
>{
>  glClear(GL_COLOR_BUFFER_BIT);
>
>  glBegin(GL_POINTS);
>  glVertexAttrib2f(0, 0.0f, 0.0f);
>  glEnd();
>
>  glutSwapBuffers();
>}
>
>int main(int argc, char **argv)
>{
>  glutInit(&argc, argv);
>  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);
>  glutInitWindowSize(256, 256);
>  glutCreateWindow("Ball");
>
>  glutDisplayFunc(draw);
>
>  initialize();
>
>  glutMainLoop();
>}

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Attachments on bug 48678: 59958 | 59959 | 59960

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