check_error();
glBindTexture(GL_TEXTURE_2D, dst_texnum);
check_error();
- glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F_ARB, width, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F, width, 1, 0, GL_RGBA, GL_FLOAT, NULL);
check_error();
glGenFramebuffers(1, &fbo);
// Now read the data back and see what the card did.
// (We only look at the red channel; the others will surely be the same.)
// We assume a linear ramp; anything else will give sort of odd results here.
- float out_data[width];
- glReadPixels(0, 0, width, 1, GL_RED, GL_FLOAT, out_data);
+ float out_data[width * 4];
+ glReadPixels(0, 0, width, 1, GL_RGBA, GL_FLOAT, out_data);
check_error();
float biggest_jump = 0.0f;
for (unsigned i = 1; i < width; ++i) {
- assert(out_data[i] >= out_data[i - 1]);
- biggest_jump = max(biggest_jump, out_data[i] - out_data[i - 1]);
+ assert(out_data[i * 4] >= out_data[(i - 1) * 4]);
+ biggest_jump = max(biggest_jump, out_data[i * 4] - out_data[(i - 1) * 4]);
}
assert(biggest_jump > 0.0);
1.0f, 1.0f,
1.0f, 0.0f
};
- float texcoords[] = {
- 0.25f, 0.0f,
- 0.25f, 0.0f,
- 0.75f, 0.0f,
- 0.75f, 0.0f
- };
GLuint vao;
glGenVertexArrays(1, &vao);
check_error();
GLuint position_vbo = fill_vertex_attribute(glsl_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
- GLuint texcoord_vbo = fill_vertex_attribute(glsl_program_num, "texcoord", 2, GL_FLOAT, sizeof(texcoords), texcoords);
+ GLuint texcoord_vbo = fill_vertex_attribute(glsl_program_num, "texcoord", 2, GL_FLOAT, sizeof(vertices), vertices); // Same data.
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
check_error();
// Now read the data back and see what the card did. (Ignore the last value.)
// (We only look at the red channel; the others will surely be the same.)
- unsigned char out_data[512];
- glReadPixels(0, 0, 512, 1, GL_RED, GL_UNSIGNED_BYTE, out_data);
+ unsigned char out_data[512 * 4];
+ glReadPixels(0, 0, 512, 1, GL_RGBA, GL_UNSIGNED_BYTE, out_data);
check_error();
int wrongly_rounded = 0;
for (unsigned i = 0; i < 255; ++i) {
- if (out_data[i * 2 + 0] != i) {
+ if (out_data[(i * 2 + 0) * 4] != i) {
++wrongly_rounded;
}
- if (out_data[i * 2 + 1] != i + 1) {
+ if (out_data[(i * 2 + 1) * 4] != i + 1) {
++wrongly_rounded;
}
}
bool check_extensions()
{
// We fundamentally need FBOs and floating-point textures.
- if (!epoxy_has_gl_extension("GL_ARB_framebuffer_object")) return false;
- if (!epoxy_has_gl_extension("GL_ARB_texture_float")) return false;
+ // FBOs are covered by OpenGL 1.5, and are not an extension there.
+ // Floating-point textures are part of OpenGL 3.0 and newer.
+ if (epoxy_gl_version() < 15 &&
+ !epoxy_has_gl_extension("GL_ARB_framebuffer_object")) return false;
+ if (epoxy_gl_version() < 30 &&
+ !epoxy_has_gl_extension("GL_ARB_texture_float")) return false;
// We assume that we can use non-power-of-two textures without restrictions.
- if (!epoxy_has_gl_extension("GL_ARB_texture_non_power_of_two")) return false;
+ if (epoxy_gl_version() < 20 &&
+ !epoxy_has_gl_extension("GL_ARB_texture_non_power_of_two")) return false;
// We also need GLSL fragment shaders.
- if (!epoxy_has_gl_extension("GL_ARB_fragment_shader")) return false;
- if (!epoxy_has_gl_extension("GL_ARB_shading_language_100")) return false;
+ if (epoxy_gl_version() < 20) {
+ if (!epoxy_has_gl_extension("GL_ARB_fragment_shader")) return false;
+ if (!epoxy_has_gl_extension("GL_ARB_shading_language_100")) return false;
+ }
// FlatInput and YCbCrInput uses PBOs. (They could in theory do without,
// but no modern card would really not provide it.)
- if (!epoxy_has_gl_extension("GL_ARB_pixel_buffer_object")) return false;
+ if (epoxy_gl_version() < 21 &&
+ !epoxy_has_gl_extension("GL_ARB_pixel_buffer_object")) return false;
// ResampleEffect uses RG textures to encode a two-component LUT.
- if (!epoxy_has_gl_extension("GL_ARB_texture_rg")) return false;
+ if (epoxy_gl_version() < 30 &&
+ !epoxy_has_gl_extension("GL_ARB_texture_rg")) return false;
// sRGB texture decode would be nice, but are not mandatory
// (GammaExpansionEffect can do the same thing if needed).
- movit_srgb_textures_supported = epoxy_has_gl_extension("GL_EXT_texture_sRGB");
+ movit_srgb_textures_supported =
+ (epoxy_gl_version() >= 21 || epoxy_has_gl_extension("GL_EXT_texture_sRGB"));
// We may want to use round() at the end of the final shader,
// if supported. We need either GLSL 1.30 or this extension to do that,
// and 1.30 brings with it other things that we don't want to demand
// for now.
- movit_shader_rounding_supported = epoxy_has_gl_extension("GL_EXT_gpu_shader4");
+ movit_shader_rounding_supported =
+ (epoxy_gl_version() >= 30 || epoxy_has_gl_extension("GL_EXT_gpu_shader4"));
return true;
}