0 broken multiple uniforms.md

These two logs show a working and broken GL call example. When there is only one uniform active, the draw call works, but when two uniforms are active, the values do not get set and are 0. The draw calls work with either one active, but not with both active. The program is all written in Rust, and uses an FFI to talk to the gl context.

broken.log

OpenGL Version 4.1
gl::GenBuffers(size:1, *buffer)
    buffer -> 1
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:1)
gl::BufferData(gl::ARRAY_BUFFER, size:9504, *data, gl::STATIC_DRAW)
    GLFloat size: 4
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:0)
gl::GenBuffers(size:1, *buffer)
    buffer -> 2
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:2)
gl::BufferData(gl::ARRAY_BUFFER, size:11904, *data, gl::STATIC_DRAW)
    GLFloat size: 4
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:0)
gl::CreateShader(shader_type:gl::VERTEX_SHADER)
gl::CreateShader -> 1
"
            #version 150
            in vec3 position;
            uniform mat4 projection;
            uniform float time;

            void main() {
                projection[0];
                gl_Position = vec4(0.05 * position + vec3(time, 0.0, 0.0), 1.0);
            }

"
gl::ShaderSource(shader:1, count:1, source:0x102238000, ptr::null())
gl::CompileShader(1)
gl::GetShaderiv(shader:1, gl::COMPILE_STATUS, *status)
    status -> 1
gl::CreateShader(shader_type:gl::FRAGMENT_SHADER)
gl::CreateShader -> 2
"
            #version 150
            out vec4 out_color;
            void main() {
                out_color = vec4(1.0, 1.0, 1.0, 1.0);
            }

"
gl::ShaderSource(shader:2, count:1, source:0x1022230c0, ptr::null())
gl::CompileShader(2)
gl::GetShaderiv(shader:2, gl::COMPILE_STATUS, *status)
    status -> 1
gl::CreateProgram() -> 3
gl::AttachShader(program:3, vertex_shader:1)
gl::AttachShader(program:3, fragment_shader:2)
gl::LinkProgram(program:3)
gl::GetProgramiv(program:3, gl::LINK_STATUS, &mut status)
    status -> 1
gl::GetActiveAttrib(program:3, attribute:0, max_name_length:127, *name_length,
                    *data_size, *data_type, *name_buffer)
    name -> "position"
    name_length -> 8
    data_size -> 1
    data_type -> gl::FLOAT_VEC3
gl::GenVertexArrays(size:1, *vao)
    vao -> 1
gl::BindVertexArray(1)
gl::BindBuffer(gl::ARRAY_BUFFER, 1)
gl::EnableVertexAttribArray(0)
gl::VertexAttribPointer(index:0, size:3, type:gl::FLOAT, normalize:gl::FALSE, stride:0,
                        offset: ptr::null())
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 2)
gl::BindVertexArray(0)
gl::GetActiveUniform(program:3, uniform:0, max_name_length:127, *name_length,
                    *data_size, *data_type, *name_buffer)
    name -> "projection"
    name_length -> 10
    data_size -> 1
    data_type -> gl::FLOAT_MAT4
gl::GetActiveUniform(program:3, uniform:1, max_name_length:127, *name_length,
                    *data_size, *data_type, *name_buffer)
    name -> "time"
    name_length -> 4
    data_size -> 1
    data_type -> gl::FLOAT
update loop time:  68.0452500237152ms
-------------------------------------------------
gl::UseProgram(program:3)
gl::BindVertexArray(1)
gl::UniformMatrix4fv(location:0, count:1, transpose:false, *GLfloat) -> [1.3728658, 0, 0, 0, 0, 1.8304877, 0, 0, 0, 0, -1.002002, -1, 0, 0, -0.2002002, 0]
gl::Uniform1f(location:1, 0.069852374)
gl::DrawElements(gl::TRIANGLES, count:2976, gl::UNSIGNED_INT, offset:0)
draw time:         2.538075961638242ms
swap buffers time: 4.07383096171543ms

working-gl-call.log

OpenGL Version 4.1
gl::GenBuffers(size:1, *buffer)
    buffer -> 1
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:1)
gl::BufferData(gl::ARRAY_BUFFER, size:9504, *data, gl::STATIC_DRAW)
    GLFloat size: 4
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:0)
gl::GenBuffers(size:1, *buffer)
    buffer -> 2
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:2)
gl::BufferData(gl::ARRAY_BUFFER, size:11904, *data, gl::STATIC_DRAW)
    GLFloat size: 4
gl::BindBuffer(gl::ARRAY_BUFFER, buffer:0)
gl::CreateShader(shader_type:gl::VERTEX_SHADER)
gl::CreateShader -> 1
"
            #version 150
            in vec3 position;
            uniform mat4 projection;
            uniform float time;

            void main() {
                // projection[0];
                gl_Position = vec4(0.05 * position + vec3(time, 0.0, 0.0), 1.0);
            }

"
gl::ShaderSource(shader:1, count:1, source:0x10d438000, ptr::null())
gl::CompileShader(1)
gl::GetShaderiv(shader:1, gl::COMPILE_STATUS, *status)
    status -> 1
gl::CreateShader(shader_type:gl::FRAGMENT_SHADER)
gl::CreateShader -> 2
"
            #version 150
            out vec4 out_color;
            void main() {
                out_color = vec4(1.0, 1.0, 1.0, 1.0);
            }

"
gl::ShaderSource(shader:2, count:1, source:0x10d4230c0, ptr::null())
gl::CompileShader(2)
gl::GetShaderiv(shader:2, gl::COMPILE_STATUS, *status)
    status -> 1
gl::CreateProgram() -> 3
gl::AttachShader(program:3, vertex_shader:1)
gl::AttachShader(program:3, fragment_shader:2)
gl::LinkProgram(program:3)
gl::GetProgramiv(program:3, gl::LINK_STATUS, &mut status)
    status -> 1
gl::GetActiveAttrib(program:3, attribute:0, max_name_length:127, *name_length,
                    *data_size, *data_type, *name_buffer)
    name -> "position"
    name_length -> 8
    data_size -> 1
    data_type -> gl::FLOAT_VEC3
gl::GenVertexArrays(size:1, *vao)
    vao -> 1
gl::BindVertexArray(1)
gl::BindBuffer(gl::ARRAY_BUFFER, 1)
gl::EnableVertexAttribArray(0)
gl::VertexAttribPointer(index:0, size:3, type:gl::FLOAT, normalize:gl::FALSE, stride:0,
                        offset: ptr::null())
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 2)
gl::BindVertexArray(0)
gl::GetActiveUniform(program:3, uniform:0, max_name_length:127, *name_length,
                    *data_size, *data_type, *name_buffer)
    name -> "time"
    name_length -> 4
    data_size -> 1
    data_type -> gl::FLOAT
update loop time:  58.89158800709993ms
-------------------------------------------------
gl::UseProgram(program:3)
gl::BindVertexArray(1)
gl::Uniform1f(location:0, 0.06052659)
gl::DrawElements(gl::TRIANGLES, count:2976, gl::UNSIGNED_INT, offset:0)
draw time:         2.1764819975942373ms
swap buffers time: 3.714050049893558ms