tests/shaders/shadersource-no-compile.c

   1 /*
   2  * Copyright © 2016 Jamey Sharp
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * \file shadersource-no-compile.c
  26  * OpenGL 4.5 Core Profile section 7.1, in the documentation for CompileShader,
  27  * says: "Changing the source code of a shader object with ShaderSource does not
  28  * change its compile status or the compiled shader code."
  29  *
  30  * This test creates a shader, compiles it, changes its source, and links it.
  31  * The spec requires rendering done with this shader to be consistent with the
  32  * old source, not the new source, since the shader isn't compiled again after
  33  * the source is changed.
  34  *
  35  * According to Karol Herbst, the game "Divinity: Original Sin - Enhanced
  36  * Edition" depends on this odd quirk of the spec. See:
  37  * https://lists.freedesktop.org/archives/mesa-dev/2016-March/109789.html
  38  */
  39 #include "piglit-util-gl.h"
  40
  41 PIGLIT_GL_TEST_CONFIG_BEGIN
  42
  43         config.supports_gl_compat_version = 20;
  44
  45         config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
  46
  47 PIGLIT_GL_TEST_CONFIG_END
  48
  49 static const char vs_text[] =
  50         "void main() { gl_Position = gl_Vertex; }";
  51
  52 /* good_fs_text uses a constant green color, while bad_fs_text uses a
  53  * constant red color, so that we can tell which version of the fragment
  54  * shader got executed. Both are distinct from the clear-color so we can
  55  * tell if the shader ran at all.
  56  */
  57
  58 static const char good_fs_text[] =
  59         "void main() { gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0); }";
  60
  61 static const char bad_fs_text[] =
  62         "void main() { gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0); }";
  63
  64 enum piglit_result
  65 piglit_display(void)
  66 {
  67         static const float green[3] = { 0.0, 1.0, 0.0 };
  68
  69         glClear(GL_COLOR_BUFFER_BIT);
  70
  71         piglit_draw_rect(-1, -1, 2, 2);
  72         if (!piglit_probe_pixel_rgb(15, 15, green))
  73                 return PIGLIT_FAIL;
  74
  75         return PIGLIT_PASS;
  76 }
  77
  78 void
  79 piglit_init(int argc, char **argv)
  80 {
  81         GLuint vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vs_text);
  82         GLuint fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, good_fs_text);
  83         const GLchar *bad_fs_texts[] = { bad_fs_text };
  84         GLuint prog;
  85
  86         /* Change the shader source, but don't recompile it before linking. */
  87         glShaderSource(fs, 1, bad_fs_texts, NULL);
  88         prog = piglit_link_simple_program(vs, fs);
  89         if (!prog)
  90                 piglit_report_result(PIGLIT_FAIL);
  91
  92         glDeleteShader(vs);
  93         glDeleteShader(fs);
  94
  95         glUseProgram(prog);
  96
  97         glClearColor(0.3, 0.3, 0.3, 0.0);
  98 }