GLSL + OpenGL Moving away from state machine -

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hey guys, started moving 1 of projects away fixed pipeline, try things out tried write shader pass opengl matrices , transform vertex , start calculating own once knew worked. thought simple task not work.

i started out shader normal fixed pipeline:

void main(void) {     gl_position = gl_modelviewprojectionmatrix  * gl_vertex;     gl_texcoord[0] = gl_multitexcoord0; }

i changed this:

uniform mat4 model_matrix; uniform mat4 projection_matrix;  void main(void) {     gl_position = model_matrix * projection_matrix * gl_vertex;     gl_texcoord[0] = gl_multitexcoord0; }

i retrieve opengl matrices , pass them shader code: 

 [material.shader bindshader];   glfloat modelmat[16];         glfloat projectionmat[16];          glgetfloatv(gl_modelview_matrix, modelmat);         glgetfloatv(gl_projection_matrix, projectionmat);           gluniformmatrix4fv([material.shader getuniformlocation:"model_matrix"], 1, gl_false, modelmat);         gluniformmatrix4fv([material.shader getuniformlocation:"projection_matrix"], 1, gl_false, projectionmat ); ... draw stuff

for reason not draw (i 95% positive matrices correct before pass them btw) ideas?

the problem order of matrix multiplication wrong. not aware operations not commutative.

the correct order should be:

projection * modelview * vertex

thanks ltjax , doug65536


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